December 15, 2019

December 15, 2019December 17, 2019 / alleghenymountainsweather / Leave a comment

December 15, 2019

Dec 15(Sun)

Snow overnight into this morning. Temps slowly falling today. Snow levels looked to be around 2200′

Bittinger 2nw Valley

MIN[23.8]—MAX[33.1]—AVERAGE MEAN[28.4]—TRUE AVERAGE[28.8]—PRECIP[.49]7am

Snowfall 2.1″ through event completion

Snowfall season to date 14.4″

Garrett College

MIN[25.1]—MAX[33.1]—AVERAGE MEAN[29.0]—TRUE AVERAGE[29.0]—PRECIP[F/S]

Canaan Heights/Davis 3SE

MIN[23.0]—MAX[29.9]—AVERAGE MEAN[26.4]—PRECIP[.86]7am

Snowfall 3.6″

Snowfall season to date 24.1″

Comments by Dave Lesher

Climate Reference Network Canaan

MIN[24.7]—MAX[30.5]—AVERAGE MEAN[27.6]—TRUE AVERAGE[28.0]—PRECIP[.27]

Cabin Mt at Bald Knob

MIN[20.5]—MAX[27.5]—AVERAGE MEAN[24.0]—TRUE AVERAGE[24.9]—PRECIP[F]

Cabin Mt-Western Sods

MIN[21.6]—MAX[28.4]—AVERAGE MEAN[25.0]—TRUE AVERAGE[25.6]—PRECIP[F]

Spruce Knob

MIN[21.0]—MAX[26.2]—AVERAGE MEAN[23.6]—TRUE AVERAGE[24.4

Snowshoe

MIN[23.2]—MAX[26.8]—AVERAGE MEAN[25.0]—TRUE AVERAGE[25.5]

Canaan Valley Refuge

MIN[24.3]—MAX[32.0]—AVERAGE MEAN[28.1]—TRUE AVERAGE[29.4]

7Springs

MIN[21.2]—MAX[31.0]—AVERAGE MEAN[26.1]—TRUE AVERAGE[25.1]

Cumberland Airport

MIN[31.1]—MAX[43.7]—AVERAGE MEAN[37.4]—TRUE AVERAGE[38.5]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

Surface features and 500mb height anomalies and flow

Pics today-

Bittinger area

Grantsville area

East to Savage Mt

Lavale

Had to post the faint rainbow in Lavale before going up to the snow

Photos by Ashley Berg at Dolly Sods

Morning update 9am

Snow activity in a varied fashion may add an additional 1-2″ as colder air seeps in through the morning. Morning temps hovering near freezing and even above below 2500-2800- in many areas except the Wv high ground in the 20 . The bigger story begins overnight into tomorrow morning.

This has a potential to be a power disrupting event in the central and eastern parts of Garrett, north into southern Pa and along the Allegheny Front and east. The cross hairs so to speak look to be eastern Garrett, parts of Allegheny and adjacent areas into Pa and down to Mt. Storm.

It would not at all be surprising if some of these areas never got above freezing with the event and it’s a event that’s moisture loaded. I would suspect the winter weather advisories may change to ice storm warnings in these areas. We shall see.

The GFS remains an outlier for the event, with much model agreeance by the various other models. The Nam, and more recently the ICON are models that typically handle this well. The ECMWF is in agreement. The GFS is on its own and will score major points if its correct. If it is, it’s a minor event winter wise.

This pushes in early morning Monday. A quick thump of snow

looks possible, a brief change to sleet. What often occurs is a precip lull that allows the column to warm and then sleet to freezing rain rapidly occurs after the snow end . Areas east, lower elevations will likely remain snow longer, the cold air depth, column is more favorable there and that is typical.

850s off the 0z ECMWF tomorrow morning

The high WV ground will be the first to change and go to plain rain and will be the less icy of the region. However, it still remains to be seen just how quick that milder air gets in there. Freezing rain should occur back to Backbone and Canaan Mts briefly at least, unlike these past ones.

From east of 219 and near Sand Flat to the Swanton area, angle to Mt.Storm, and points north, northeast this looks to be a duration ice event. Stay tuned.

Jump to the models. My favorite in the setup as it performs well . The 3km Nam

6z 3km Nam

2m temps

Closer look at Garrett(central time on this map)

0z ECMWF

2m temps

MSLP/6HR/PRECIP

6z ICON

2m temps

HRDPS(Short range Canadian)

2m temps

overdone very likely

0z Canadian

Ice totals

Now the GFS. A much milder outlier

WPC OUTLOOK

For freezing rain accretion

Will post more through today. Updates etc as this is a potential major event in some areas.

December 14, 2019

December 14, 2019January 2, 2020 / alleghenymountainsweather / Leave a comment

December 14, 2019

Dec 14(Sat)

Rainy morning, some pockets of ice in the deep valleys east yet this morning. Cold air changing rain to snow across the high ground midday, afternoon. Light accumulations by nightfall.

Bittinger 2nw Valley

MIN[30.9]—MAX[42.3]—AVERAGE MEAN[36.6]—TRUE AVERAGE[34.1]

Snowfall season to date 12.3″, will add new tally at recording time tomorrow a.m

Garrett College

MIN[30.6]—MAX[43.1]—AVERAGE MEAN[36.8]—TRUE AVERAGE[36.2]—PRECIP[.39]

Canaan Heights/Davis 3SE

MIN[27.4]—MAX[44.9]—AVERAGE MEAN[36.1]—PRECIP[.24]7am

Snowfall season to date 20.5″. Todays tally included in tomorrow a.m total

Comments by Dave Lesher

Climate Reference Network Canaan

MIN[28.4]—MAX[45.5]—AVERAGE MEAN[37.0]—TRUE AVERAGE[36.8]—PRECIP[.72]

Cabin Mt at Bald Knob

MIN[25.5]—MAX[42.6]—AVERAGE MEAN[34.0]—TRUE AVERAGE[33.9]—PRECIP[.62] *frozen late as with all non heated tipping bucket sites

Cabin Mt-Western Sods

MIN[26.1]—MAX[43.7]—AVERAGE MEAN[34.9]—TRUE AVERAGE[34.6]—PRECIP[.50]

Spruce Knob

MIN[24.6]—MAX[41.4]—AVERAGE MEAN[33.0]—TRUE AVERAGE[32.7]—PRECIP[.31]

Snowshoe

MIN[25.4]—MAX[42.1]—AVERAGE MEAN[33.7]—TRUE AVERAGE[33.1]

Canaan Valley Refuge

MIN[29.8]—MAX[47.5]—AVERAGE MEAN[38.6]—TRUE AVERAGE[38.1]

7Springs

MIN[28.3]—MAX[41.8]—AVERAGE MEAN[35.0]—TRUE AVERAGE[34.0]

Cumberland Airport

MIN[32.0]—MAX[44.7]—AVERAGE MEAN[38.3]—TRUE AVERAGE[36.6]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

Surface features and 500mb height anomalies and flow

Videos today from webcams

Post generated 7am 12/14/19

Icy pockets remain in some of the deeper valleys on the east side of the Alleghenies at the time of this writing shortly before 7am this morning. Traveling in that area, use caution. Otherwise today, we watch for the rain to snow transition as colder air from the west encroaches on the area.

Modeling is generally showing this to occur late morning, early afternoon for the WV high ground, and occurring shortly thereafter north across Garrett, Preston, and the southern Pa high ground.

From 12pm today through 4pm Sunday, this appears to be a 3-6″ snowfall for the Wv high ground.(3000’+) As always lean low to mid range and if it performs well, the upper range can be reached. 2-4″ for Garrett, Preston and north into the southern Pa high ground above 2500′. Slightly lower amounts under 2500′. Again, low to mid range looks likely and after some weird forecast last night, the NWS has came around to close to this, but holding it low and at the time of this writing, holding this under winter weather advisory criteria and that may give travelers in this area a false sense of what road conditions will be…

As we go into Monday, the next system is quickly upon us. Once again, the region will be quartered up as some will remain with wintry precip and others to rain.

We all should begin as a round of snow, that transitions briefly to sleet, then to freezing rain and then plain rain.(not all) How long the snow holds on, is a bit of a question mark. It may be a quick brief thump(1-2″) a relaxing in precip, and that allows a warm column to get in aloft SW to NE. This transitions the Wv high ground quickly to a mix and to rain.

However the typical, classic, common, normal, routine, holdouts, The Allegheny Front, this looks to be Spruce Knob and north and duration is longer north, and north central Garrett County, points north, east, this looks to be a duration of a wintry mess. The models will help display that, and if you live here, you’ve seen this play out so many times over the years. This is the high ground and again the lower elevations east involved. Lots of times these systems will hold snow/sleet longer east side of Savage Mt to Frostburg and Lavale with greater accumulations there, than say Grantsville. (Sleet looks minimal with this particular event)That’s something to watch for Monday.

Ice accretion does look to be a concern from the Bittinger area, and points east, north east. Especially the high ground and east facing areas as a strong east wind occurs during this time. With a strong east wind, temps do not just magically spike above freezing. The common NWS error is to forecast the warm air into the typical freeze zone much to soon. Sometimes anywhere from 2 hours to 12 hours to soon. Granted, things have time to adjust yet, but already their Monday forecast looks too soon to rain. I would rather, in these instances have a forecast call for ice a little longer(Tuesday a.m even) than expected for safety purposes in which what winter forecast are for than call for it to end sooner than it does than put people out in about making plans while conditions are still poor.

So, let’s jump to the models. Both the weekend event and early week included:

0z ECMWF

2M Temps

MSLP/6HR/PRECIP TYPE

10m Wind Gust

Snowfall through the weekend event

Ice through the Monday event – too note, this is likely overdone.

6z GFS

2m Temps

MSLP/6HR/PRECIP TYPE

Snowfall amounts off the weekend event

Ice through the Monday event-looks underdone

0z Canadian

2m Temps

MSLP/6HR/PRECIP TYPE

Snowfall off the weekend event

Ice for the Monday event

06z 12km Nam

2m Temps

MSLP/6HR/PRECIP TYPE

Snowfall off the weekend event-Nam is notorious for putting out to much liquid with systems. Not a strong suit of the model

Ice for the Monday event. Having said about to much liquid with systems, by that I mean precip in general, the Nam does agree some with the ECMWF with this event. Saying is, when then NAM and ECMWF , pay attention

6z ICON

This model is up there with the Nam in handling temperatures with these east flow/cold air damming events

2m Temps

adding the wind streamers with temps, that east flow Monday. Again, those classic areas, temps do not magically rise very fast.

Let’s hop to the WPC outlook for the snow event this weekend and ice early week.

Snowfall probabilities

48 hr 4″ probability

WPC Ice potential

.10

.25

.50

New NWS forecast, wording is much improved for the weekend event, over the strange wording from last night.

Few weeks ago I made a post about this, freezing rain to rain to snow pattern. Its held. Several years ago Bob Leffler had told me, he was taught to watch the 500mb heights off Miami. When you see that ridge build, do not plan on a consistent snowy pattern in the Wv high country, and basically look for what we are seeing with this current pattern. The SW flow aloft is not conducive for anything more than brief hots of snow, cold, followed by a warm intrusion aloft with the following system and repeat. Well, that rule, which I would call it a rule, has worked nearly 100%.

Heres the 500 for early week

590 heights off Miami is not what you want to see in the WV high ground if you want winter to hold its ground

That said, there are signs this relaxes and other teleconnections become more favorable down the road. Unfortunately, models just aren’t that good at it. This year, the setup is very December 2013ish. Without the blowtorch days…and we all should remember where January 2014 went…

December 13, 2019

December 13, 2019January 2, 2020 / alleghenymountainsweather / Leave a comment

December 13, 2019

Dec 13(Fri)

A variety of weather in the area. The classic ice zones got some light glaze, the valleys on the east side of the Mts picked up a quicker glaze in the morning that lead to very slick conditions. Temps varied as you’ll see below and the RTMA gives a good handle. Some deeper colder valleys held below 32.

Bittinger 2nw Valley

MIN[22.5]—MAX[34.0]—AVERAGE MEAN[28.2]—TRUE AVERAGE[29.4]

Snowfall season to date 12.3″

Garrett College

MIN[23.2]—MAX[38 4]—AVERAGE MEAN[30.8]—TRUE AVERAGE[31.8]—PRECIP[.07]

Canaan Heights/Davis 3SE

MIN[25.0]—MAX[44.0]—AVERAGE MEAN[34.5]—PRECIP[T]7am

Snowfall season to date 20 5″

Climate Reference Network Canaan

MIN[24.6]—MAX[45.3]—AVERAGE MEAN[34.9]—TRUE AVERAGE[37.3]—PRECIP[.11]

Cabin Mt at Bald Knob

MIN[28.6]—MAX[42.8]—AVERAGE MEAN[35.7]—TRUE AVERAGE[36.1]—PRECIP[.13]

Cabin Mt-Western Sods

MIN[20.7]—MAX[43.2]—AVERAGE MEAN[31.9]—TRUE AVERAGE[35.6]—PRECIP[.14]

Spruce Knob

MIN[18.9]—MAX[39.2]—AVERAGE MEAN[29.0]—TRUE AVERAGE[32.3]—PRECIP[.16]

Snowshoe

MIN[20.8]—MAX[43.0]—AVERAGE MEAN[31.9]—TRUE AVERAGE[34.5]

Canaan Valley Refuge

MIN[16.3]—MAX[45.7]—AVERAGE MEAN[31.0]—TRUE AVERAGE[36.5]

7Springs

MIN[21.0]—MAX[36.0]—AVERAGE MEAN[28.5]—TRUE AVERAGE[28.6]

Cumberland Airport

MIN[25.7]—MAX[33.0]—AVERAGE MEAN[29.3]—TRUE AVERAGE[30.2]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

(Forgot to download from the nullschool site, so a different version today since nullschool does not archive)

Surface features and 500mb height anomalies and flow

pics today-

Lavale to Frostburg

Cold air loves to hang in these low valleys in this area after a departing cold air mass in place

Savage Mt area

Grantsville to Bittinger area

Initial very light glaze, high valleys held cold. Not as good as the deeper valleys do, but the high valleys still cooler than the high ground from in this area and west

Deep Creek Lake

Smooth area is a thin ice cover

Cranesville area

Far enough west, not nearly as ice prone in these setups

The Yough-Sang Run

Colder Deep Valleys east

Late evening update: 12/13/19

Some quick views of the latest model guidance for snowfall that begins first in the Wv high ground midday, early afternoon tomorrow, early to mid afternoon north of Canaan.

Overall looks like a 3-6″ event Wv high ground, as always I lean low to mid and allow for a good performance to achieve the high en .

2-4″ Garrett, Preston into the Southern Pa high ground.

18z ECMWF

18z GFS

12z Canadian

Some very bizarre wording from the Pitt NWS. As great as their service has been early on this season, the past few days has just been a tad strange. The misunderstanding of how the ice setup this morning works, now this…

Freezing rain possibly mixed with a snow shower tomorrow night, 1-3″????!!! That may be the first in recorded history for the area.

For Garrett… lots of areas colder than forecast mins for daytime maxes today. Temps slow to rise overnight…the mins are and will be colder than forecast.

Charleston more in line with modeling on their end

December 12, 2019

December 12, 2019December 14, 2019 / alleghenymountainsweather / Leave a comment

December 12, 2019

Dec 12(Thurs)

High overcast, east flow

Bittinger 2nw Valley

MIN[10.9]—MAX[31.7]—AVGERAGE MEAN[21.3]—TRUE AVERAGE[22.9]—PRECIP[0]

Garrett College

MIN[14.1]—MAX[35.3]—AVERAGE MEAN[24.7]—TRUE AVERAGE[24.9]

Canaan Heights/Davis 3SE

Will be filled in later

Climate Reference Network Canaan

MIN[12.2]—MAX[35.6]—AVERAGE MEAN[23.9]—TRUE AVERAGE[24.2]—PRECIP[0]

Cabin Mt at Bald Knob

MIN[12.2]—MAX[31.5]—AVERAGE MEAN[21.8]—TRUE AVERAGE[22.5]—PRECIP[0]

Cabin Mt-Western Sods

MIN[13.6]—MAX[30.6]—AVERAGE MEAN[22.1]—TRUE AVERAGE[21.3]—PRECIP[0]

Spruce Knob

MIN[11.8]—MAX[26.8]—AVERAGE MEAN[19.3]—TRUE AVERAGE[19.8]

Snowshoe

MIN[14.2]—MAX[32.0]—AVERAGE MEAN[23.1]—TRUE AVERAGE[22.5]

Canaan Valley Refuge

MIN[5.2]—MAX[35.6]—AVERAGE MEAN[20.4]—TRUE AVERAGE[22.5]

7Springs

MIN[13.8]—MAX[30.4]—AVERAGE MEAN[22.1]—TRUE AVERAGE[21.0]

Cumberland Airport

MIN[21.3]—MAX[38.6]—AVERAGE MEAN[29.9]—TRUE AVERAGE[30.4]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Void

Satellite

Flow

Surface features and 500mb height anomalies and flow

Afternoon update:

Afternoon thoughts based off the latest model runs-

Light precip pushes in to the southern areas in the region in the morning. Main concern is a light freezing rain glazing things over. This pushes north through the day. Overall precip is mostly light. Tomorrow night, any areas in the classic high elevation ice zones(those same spots that’s saw ice on Dec 1) that are typical holdouts for freezing rain, those areas will rise +32 early in the night. The remaining areas to watch for freezing rain turns to the deeper valleys, the Savage River valleys and valleys mainly east of the Allegheny Front. Those pockets may hold below freezing into Saturday morning.

Temps creep up across the board post dawn Saturday, rain into the afternoon region wide. Early to mid afternoon that rain begins to transition to snow, first across the WV high ground, then north into Preston, Garrett and high ground in southern Pa.

Saturday night- as of now, a steady period of snow looks likely, with periods of varied intensity into Sunday with a tapering down through the day. Temps on Sunday holding 20s, Wv high ground, upper 20s lower 30s to 2500′ lower to mid 30s below 2500. Forecast mentioning rain mixing in during the day on Sunday are very very unlikely. 850temps(near 5000′, roughly near the highest Wv areas) are modeled -5c to -8c. When its precipitating across the high ground, temps at 5000′ of 17f to 23f, you are not changing to liquid. There is no diurnal and even less so on December 15th.

A struggle within the modeling has been precipitation amounts and therefore snow fall amounts. Lots of agreement currently in place within the models and that has not been all that common. A early call, if you can say Thursdsy afternoon prediction for Saturday night into Sunday is early, is a 3-6″ snowfall across the Wv high ground, with 2-4″ with higher pops across Garrett, Preston, and southern high ground of Pa.

Likely tweaks on timing and amounts will occur.

A look at the models and the amount of agreement. These models will not pick up on those isolated, secluded valleys that remain below freezing. The mesoscale 3km Nam will do better(not perfect), and will post more with it tomorrow morning. It does much better than the HRRR which has a exaggerated consistent warm bias.

12z ECMWF

2m Temps

850 temps

MSLP/6HR/PRECIP TYPE

Freezing rain

Snowfall

12z GFS

2m Temps

850 Temps

MSLP/6HR/PRECIP

Freezing rain

Snowfall

12z Canadian

MSLP/6HR/PRECIP

Snowfall

Again, these are model runs, only tools, not the gospel. Stay tuned

WPC OUTLOOK:

Ice- which for the southern areas mainly comes in early tomorrow, and then watch for lingering cold pockets tomorrow night in the deeper valleys. More widespread initially.

WPC Freezing rain maps.

NWS Advisories

NWS products

18z GFS snowfall through Sunday 7pm

18z ECMWF snowfall

December 11, 2019

December 11, 2019January 2, 2020 / alleghenymountainsweather / Leave a comment

Dec 11(Wed)

Morning light snow, otherwise clearing and windy. Remaining cold.

Bittinger 2nw Valley

MIN[17.1]—MAX[23.5]—AVERAGE MEAN[20.3]—TRUE AVERAGE[21.0]

Snowfall through event completion at 8:30am of .4″ new

Season to date total snowfall of 12.3″

Garrett College

MIN[16.7]—MAX[23.9]—AVERAGE MEAN[20.3]—TRUE AVERAGE[21.0]—PRECIP[F]

Canaan Heights/Davis 3SE

MIN[13.9]—MAX[20.0]—AVERAGE MEAN[16.9]—PRECIP[.53]7am

Snowfall 1.3″ new snowfall

Season to date total snowfall 20.5″

Comments by Dave Lesher

Climate Reference Network Canaan

MIN[15.0]—MAX[21.8]—AVERAGE MEAN[18.4]—TRUE AVERAGE[18.3]—PRECIP[0]

Cabin Mt at Bald Knob

MIN[10.6]—MAX[18.0]—AVERAGE MEAN[14.3]—TRUE AVERAGE[13.9]—PRECIP[F]

Cabin Mt-Western Sods

MIN[11.8]—MAX[17.8]—AVERAGE MEAN[14.8]—TRUE AVERAGE[14.8]—PRECIP[F]

Wind gust max 41.3mph

Spruce Knob

MIN[9.5]—MAX[16.3]—AVERAGE MEAN[12.9]—TRUE AVERAGE[13.0]—PRECIP[F]

Snowshoe

MIN[10.0]—MAX[16.7]—AVERAGE MEAN[13.3]—TRUE AVERAGE[13.9]

Canaan Valley Refuge

MIN[16.5]—MAX[23.0]—AVERAGE MEAN[19.7]—TRUE AVERAGE[19.4]

7Springs

MIN[13.2]—MAX[20.4]—AVERAGE MEAN[16.8]—TRUE AVERAGE[17.2]

Cumberland Airport

MIN[28.2]—MAX[35.4]—AVERAGE MEAN[31.8]—TRUE AVERAGE[31.3]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

Surface features and 500mb height anomalies and flow

Pics today-

Bittinger area

Deep Creek Lake area and south

Grantsville area

Frostburg-Savage Mt area

Centennial Park Tucker County Rt 219

Keysers Ridge

Evening update: 7pm 12/11/19

A quick recap and a look ahead. The brief snow event last night ended up on the minimal side of expectations. Totals remained at the low end of expected amounts and in many cases just under. No area overperformed.

Reported amounts

Looking ahead-

Winds die off overnight, valley temps should fall off pretty good before dawn. Cold across the board and holding chilly tomorrow. Friday, that will see some moisture, pressing north from the Carolinas. It will be fighting low level dry air initially and likely radar will be showing virga for awhile. Across the southern Alleghenies, over into the deeper valleys into VA, when precip does reach the ground, albeit light, there will likely be areas of light freezing rain and that coming on the heels of a few cold days, may give some surface areas a light glazing and create slick conditions.

As we go through Friday this very light precip presses north. Some light freezing rain potential will exist into the northern Alleghenies, mainly the classic areas of north central Garrett and points north and east as we go into late Friday into the night. Overnight and prior to dawn Saturday, all areas except the deeper valleys east of the Alleghenies should rise above freezing. That’s when a period of steady rain looks to push in. Those deeper valleys need watched. This is not the same as the previous ice setup in this regard. This is coming in over a colder airmass, and that low level cold air likes to hang in those deep valleys.

On Saturday morning, steady rain, and by late morning to early afternoon max temps f upper 30s, lower 40s will have been reached and slowly falling temps through the remainder of the day with rain transitioning to snowfall. Beginning first across the Wv high ground, with snow continuing into Sunday morning in a bit more of a classic upslope vs this recent rain to snow transition.

Accumulations look likely, with potential of several inches in favored upslope areas.

Friday temps into the weekend off the 3km Nam, and the ICON model with windstream. The ICON handles these situations well, but the 3km Nam being king. That said, it’s likely a tad too cold. Beginning with a zoomed in look at Garrett and then expanded back with another look at the 3km Nam, with the ICON last

A look at the precip type off the 3km Nam(precip amount a weakness of the model)

Precip type of the 18z GFS, which is a larger grid than the high res Nam.

Snowfall amounts Saturday night into Sunday off the 12z ECMWF and 18z GFS

December 10, 2019

December 10, 2019December 11, 2019 / alleghenymountainsweather / Leave a comment

Dec 10(Tues)

Mild, wet early ,falling temps , snow late. High water in areas, some small creeks over backfill in areas that saw 1-2″ of rain.

Bittinger 2nw Valley

MIN[22.1]—MAX[52.1]—AVGERAGE MEAN[37.1]—TRUE AVERAGE[39.9]—PRECIP[1.21]7am

Snowfall season to date 11.9″

Garrett College

MIN[22.4]—MAX[53.3]—AVGERAGE MEAN[37.8]—TRUE AVERAGE[39.9]—PRECIP[.72]

Canaan Heights/Davis 3SE

MIN[17.7]—MAX[51.8]—AVG[34.7]

Snowfall season to date 19.2″(todays will be added on totals tally tomorrow)

Comments by Dave Lesher

Climate Reference Network Canaan

MIN[19.7]—MAX[53.7]—AVERAGE MEAN[36.7]—TRUE AVERAGE[39.2]—PRECIP[.64]

Cabin Mt at Bald Knob

MIN[16.0]—MAX[48.9]—AVGERAGE MEAN[32.4]—TRUE AVERAGE[35.8]—PRECIP[.62]

Cabin Mt-Western Sods

MIN[15.9]—MAX[50.5]—AVERAGE MEAN[33.2]—TRUE AVERAGE[36.6]—PRECIP[.28]

MAX GUST [47.4MPH]

Spruce Knob

MIN[16.3]—MAX[44.8]—AVERAGE MEAN[30.5]—TRUE AVERAGE[35.4]—PRECIP[.33]

Snowshoe

MIN[15.4]—MAX[48.7]—AVERAGE MEAN[32.0]—TRUE AVERAGE[35.4]

Canaan Valley Refuge

MIN[21.0]—MAX[54.5]—AVERAGE MEAN[37.7]—TRUE AVERAGE[40.5]

7Springs

MIN[18.2]—MAX[52.1]—AVERAGE MEAN[35.1]—TRUE AVERAGE[35.4]

Cumberland Airport

MIN[32.3]—MAX[56.3]—AVERAGE MEAN[44.3]—TRUE AVERAGE[42.1]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satelite

Flow

Surface features and 500mb height anomalies and flow

Blackwater River at Davis

Cassleman River at Grantsville

Pics today-

Bittinger area

McHenry area afternoon

Swallow Falls by Derek Buckel

Afternoon update 1:15pm 12/10/19

December 10, 2019

Colder air pushing back in after the mild 24 hours and in some areas 48 hours. The mild rain pretty well wiped out the snow cover that existed in the high ground, except for a few patches here and there. Now the question is, how much returns?

Thoughts have no changed drastically off this doodle map posted from yesterday. One thing to note, a strong leaning to the lower side of the numbers are in play. East of the Alleghenies, still a wild card.

The models

Here is yesterdays 12z ECMWF

Today’s 12z ECMWF

Not a great deal of change in the Euro.

Yesterday 12z GFS

Today’s 12z GFS

more in line with the ECMWF in lowering totals, but likely overdone yet in the immediate area.

Yesterdays 12z Nam vs today’s

showing that area east much better and that area still may be the area the models adjust too later on.

The NWS forecast yesterday

The NWS forecast today

While overall I agree with local totals being lowered and still in the low range of the window on the doodle map, the NWS, mainly Sterling sticks the best accumulation in between where most modeling has it.

Sterlings forecast discussion

Sleeper area in the event still remains the Blue Ridge and north into Pa, east of the Alleghenies.

December 9, 2019

December 9, 2019December 11, 2019 / alleghenymountainsweather / Leave a comment

December 9, 2019

Dec 9(Mon)

Cloudy, some fog, colder valleys. Even some of the higher more protected valleys held much colder through part of the day, enough some there may have been a few pockets of freezing. Some reports of the deeper valleys east,,reported some sleet pellets early. Temps became much warmer over all the high ground, with moderate rains, while east of the mountains held cooler

Bittinger 2nw Valley

MIN[29.7]—MAX[53.0]—AVG MEAN[41.3]—TRUE-AVERAGE[39.7]—PRECIP[.09]7am

Garrett College

MIN[36.3]—MAX[54.3]—AVG MEAN[45.3]—TRUE AVERAGE[46.1]—PRECIP[.91]

Canaan Heights/Davis 3SE

MIN[37.1]—MAX[51.8]—AVG MEAN[44.4]—PRECIP[.03]7am

Climate Reference Network Canaan

MIN[34.3]—MAX[53.4]—AVERAGE MEAN[43.9]—TRUE AVERAGE[43.2]—PRECIP[.57]

Cabin Mt at Bald Knob

MIN[37.4]—MAX[48.2]—AVG MEAN[42.8]—TRUE AVERAGE[43.2]—PRECIP[.72]

Cabin Mt – Western Sods

MIN[37.8]—MAX]50.0]—AVG MEAN[43.9]—TRUE AVERAGE[44.1]—PRECIP[.54]

Spruce Knob

MIN[32.0]—MAX[44.1]—AVG MEAN[38.0]—TRUE AVERAGE[38.9]—PRECIP[.46]

Snowshoe

MIN[35.2]—MAX[48.2]—AVG MEAN[41.7]—TRUE AVERAGE[41.1]

Canaan Valley Refuge

MIN[31.8]—MAX[54.0]—AVG MEAN[42.9]—TRUE AVERAGE[43.8]

7Springs

MIN[37.6]—MAX[51.7]—AVG MEAN[44.6]—TRUE AVERAGE[44.6]

Cumberland Airport

MIN[32.0]—MAX[39.0]—AVG MEAN[35.5]—TRUE AVERAGE[35.6]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

Surface features and 500mb height anomalies and flow

pics today

Bittinger area

Grantsville area

Savage Mt to Cumberland

The best view of the high ground warmth to lower elevation colder air(low areas in the fog)

Upcoming snow event, more questions than answers….

As we transition back to cold tomorrow, the setup as of 1pm today leaves more questions yet than answers. As rain transitions to snow, in the afternoon, is it fleeting and light,or moderate and lingering into the early overnight? I’m not sure those can be answered yet. Any forecast at this point from anywhere, comes with a low confidence forecast.

This isn’t the traditional cold front crossing tomorrow, it’s a anafront

http://rammb.cira.colostate.edu/wmovl/vrl/tutorials/satmanu-eumetsat/SatManu/CMs/Cf/backgr.htm

These setups can produce heavier snow east of the Alleghenies vs right over the Alleghenies. Really depends on where they slow down and stall. As of now, this looks to cross the Allegenies fairly quickly with the greatest moisture available Canaan and south. Very low confidence though I must add. Once it cross the Alleghenies, and gets 50-75 miles east, slows down, a deepening may occur, more vertical motion and it snows to beat the band. This is not the classic downslope, where the Alleghenies rob the moisture setup. A lot of ingredients are at play. How those ingredients become mixed, is very unclear. Modeling is still all over the place. As timing, how much the trough deepens, speed, etc will play a big role. Currently the models vary in this, quite significantly I might add. Enough so, the snow maps off the models vary greatly. As seen:

This within 36 hours is a wide range. I tend to like this type of setup for amounts on my doodle map. It’s a bit of a blend, but more classic to the setup. That is tricky. Ours occurs fairly rapidly after the changeover. Over east it occurs overnight. This has a very high boom or bust potential.

Here is the current NWS office forecast thinking.( I doodled my map prior to seeing theirs, so seeing some similarities was encouraging). There is office discrepancy there as the Blacksburg office sees this a little differently than Charleston and Sterling. Overall though, I like it, except I think the areas east, could boom with this more. With any significant changes, slowing of the front, timing, I will update.

For snow forecast, these are as tough as they come. They often have surprises and the greatest boom or bust with this looks in my opinion to be the Blue Ridge, Martinsburg, Hagerstown, Chambersburg and up into Pa. This would not be surprising to see it overperform there.

Late week event, that has a icy look to start, then rain, then snow. The long range pattern keeps regenerating that SE Ridge and that does not bode well for sustained winter weather or straight snow events. When you see a 500mb like this, that’s a big UGH to winter lovers

They tend to produce systems like we have been seeing…

December 8, 2019

December 8, 2019December 9, 2019 / alleghenymountainsweather / Leave a comment

December 8, 2019

Dec 8(Sun)

SE flows dimmed sun. Pretty much the theme

Bittinger 2nw Valley

MIN[15.8]—MAX[39.0]—AVG[27.4]—PRECIP[0]7am

Snowfall season to date 11.9″

Garrett College

MIN[25.2]—MAX[41.6]—AVG[33.4]—PRECIP[0]

Canaan Heights/Davis 3SE

MIN[22.9]—MAX[41.0]—AVG[31.9]—PRECIP[0]7am

Snowfall season to date 19.2″

Climate Reference network Canaan

MIN[19.1]—MAX[40.8]—AVG[30.0]—PRECIP[0]

Cabin Mt at Bald Knob

MIN[23.7]—MAX[39.0]—AVG[31.3]—PRECIP[0]

Cabin Mt-Western Sods

MIN[22.5]—MAX[40.6]—AVG[31.5]—PRECIP[0]

Spruce Knob

MIN[21.2]—MAX[33.8]—AVG[27.5]—PRECIP[0]

Snowshoe

MIN[22.3]—MAX[38.5]—AVG[30.4]

Canaan Valley Refuge

MIN[9.3]—MAX[43.5]—AVG[26.4]

7Springs

MIN[22.5]—MAX[39.5]—AVG[31.0]

Cumberland Airport

MIN[19.0]—MAX[42.0]—AVG[30.5]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

I68 at Savage Mt vs I68 at the Md/Wv line

SE flow results.

RTMA

Radar

Void

Satellite

Flow

Surface features and 500mb height anomalies and flow

Webcam images today-

December 7, 2019

December 7, 2019December 9, 2019 / alleghenymountainsweather / Leave a comment

December 7, 2019

Dec 7(Sat)

A mostly sunny day, clear cold start. Best upslope areas retaining a snow cover.

Bittinger 2nw Valley

MIN[16.0]—MAX[32.0]—AVG[24.0]—PRECIP[.09]7am

Garrett College

MIN[20.5]—MAX[34.9]—A[27.7]—PRECIP[0]

Canaan Heights/Davis 3SE

MIN[13.9]—MAX[32.0]—AVG[22.9]—PRECIP[.26]7am

CRN-Canaan

MIN[18.2]—MAX[32.5]—AVG[25.3]—PRECIP[0]

Cabin Mt at Bald Knob

MIN[14.2]—MAX[28.4]—AVG[21.3]—PRECIP[0]

Cabin Mt-Western Sods

MIN[17.1]—MAX[29.3]—AVG[23.2]—PRECIP[0]

Spruce Knob

MIN[15.6]—MAX[28.0]—AVG[21.8]—PRECIP[0]

Snowshoe

MIN[17.1]—MAX[31.8]—AVG[24.4]

Canaan Valley Refuge

MIN[10.4]—MAX[33.4]—AVG[21.9]

7Springs

MIN[19.3]—MAX[28.7]—AVG[24.0]

Cumberland Airport

MIN[22.8]—MAX[42.4]—AVG[32.6]

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Void of precip today

Satellite

Flow

Surface features and 500mb height anomalies and flow

Pics today-

The Bittinger area

Deep Creek Lake to Oakland area

Grantsville area

December 6, 2019

December 6, 2019December 7, 2019 / alleghenymountainsweather / Leave a comment

December 6, 2019

Dec 6(Fri)

After an awesome sunrise, and a cold valley night, clouds rolled in and temps quickly rose into 40s by midday before backsliding in the afternoon. Light precip began, that was some snow up high, above 4000′, and for a time snow mixed to 2500′, but that went to liquid and remained so through 7pm to about 3500 it appeared. Snowshoe recieved a coating.

Bittinger 2nw Valley

MIN[18.1]—MAX[46.6]—AVG[32.3]—PRECIP[0]7am

Snowfall season to date 11.9″

Garrett College

MIN[28.5]—MAX[46.4]—AVG[37.4]—PRECIP*[.19]

Precip- melt + precip today

Canaan Heights/Davis 3SE

MIN[24.4]—MAX[40.9]—AVG[32.6]—PRECIP[T]7am

Snowfall season to date 19.2″

CRN-Canaan

MIN[27.8]—MAX[43.1]—AVG[35.5]—PRECIP[.21]

Cabin Mt at Bald Knob

MIN[24.6]—MAX[38.1]—AVG[31.3]—PRECIP*[.26]

*melt plus daily precip

Cabin Mt-Western Sods

MIN[24.6]—MAX[39.9]—AVG[32.2]—PRECIP*[.17]

*melt plus daily precip

Spruce Knob

MIN[22.6]—MAX[36.3]—AVG[29.4]—PRECIP*[.01]

Snowshoe

MIN[22.6]—MAX[38.5]—AVG[30.5]

Primary precip today-snow

Canaan Valley Refuge

MIN[5.7]—MAX[43.5]—AVG[24.6]

7Springs

MIN[23.4]—MAX[42.6]—[33.0]

Cumberland Airport

The Valley vs Cabin Mt

Canaan area temps

Comparison view

RTMA

Radar

Satellite

Flow

Surface features and 500mb height anomalies and flow

webcam videos today

Snowshoe

Canaan

Wisp

33 east of Harman at the divide

Morning outlook update:

A WIDE variety of temperatures this morning, as low as a single digit lonely 6° at the Canaan Valley Refuge station in the northern end of Canaan Valley, while Cabin Mt is sitting at 32°, other sites in the area vary from upper teens to the upper 30s.

As we go through the morning, all of these will become more uniform and rise into the upper 30s to mid 40s. Relatively low dew points in tack, however the snowpack will likely compact a get a bit sticky. As we progress into the afternoon, some precip will try to push in and that initially will cause evaporative cooling and daytime max temps likely will be reached late morning to early afternoon with temps then slowly backsliding to reach the dewpoints in the low to mid 30 .

Precip should begin to reach the surface later in the day. Above 2500, this may begin briefly as rain drops but transition to light snow activity that may put down a new coating in spots, with some light accumulation possible above 3000-3500. Minor event, snow accumulation +/- 1″. If anything more impressive than that occurs, I will update.

Here is the 6z ECMWF temps today and tonight ,

The mild surge this morning evident

6z ECMWF MSLP/6HR/PRECIP TYPE

Precip with this minor event

We chill down a notch tomorrow vs today. Sunday a mild surge with eastern zones holding chillier. Monday is a ruination day for winter lovers, and some of the winter dreams returning on Tuesday.