Heavy rains early, a break, with more rains mid morning, showers through the afternoon and a transition to graupel, ice pellet, flake evening. Also some fog across the high ground at times. Eventful.
Bittinger 2NW Valley
another 1.92 since last evening at 6pm. Since Saturday 4.90″
Dyacon Data Below
Rock Lodge Rd near The Glades morning Rock Lodge Rd morning North branch of the Cassleman Rock Lodge Rd morning West of Bittinger morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning South end Amish Rd morning Bittinger morning Bittinger morning Foxtown Rd afternoon West of Bittinger afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon “experimental spot”Bittinger 2NW Valley afternoon “dry pee spot”Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley evening Near old Cherry Glade Church evening
Garrett County Airport
Mchenry morning By Garrett College morning Mosser Rd morning Cherry Creek at Mosser Rd morning Cherry Creek at Mosser Rd morning Mosser Rd afternoon Mosser Rd at Cherry Creek afternoon Mosser Rd at Cherry Creek afternoon Mosser Rd at Bear Creek evening
Top of Wisp
Canaan Heights/Davis 3SE
7am to 7am data mmts coop BP
Climate Reference Network Canaan
Atop Canaan Ski area
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Cabin Mt at Bald Knob
Cabin Mt-Western Sods
Spruce Knob
Canaan Valley Refuge
Mt.Davis
Snowshoe
Petersburg Grant County Airport
Elkins Airport
SITE COMPARISON
Dy007-Canaan Valley Refuge 3150′, Dy008-Bittinger 2nw Valley 2600′, Dy002-Cabin Mt at Bald Knob 4350′, Dy003-Cabin Mt-Western Sods 4035′, Dy004-Spruce Knob 4820′, Cvpw2-Climate Reference Network Canaan 3380′, KW99-Petersburg Grant County Airport 961, K2G4 Garrett County Airport 2933′, KCBE Cumberland Airport 774′, KEKN Elkins Airport 1985′, KMGW Morgantown Airport 1227′, PMN16-Mt.Davis 3038′, KDCA-Reagan National 15′, G1472 Snowshoe 4500′, F0183 Burkes Garden 3050′
The Valley vs Cabin Mt
Bittinger 2NW Valley vs Mt.Davis
Canaan area temps
High Ground Comparison
Up High and Down Low
Up High, High Valley, Low Valley
Subbed in new Frostburg mesonet for Cumberland stations that’s offline
Rounds of rain, rounds of storms, colder push and snow
Rainfall amounts since Saturday in the 1-3″ range in the Alleghenies with more to go. Here is radar after 8pm
Areas of heavy rain, storms, severe storms that carry severe thunderstorm warnings and a Tornado warning west and a Tornado watch area over much of western West Virginia.
The severity of the storms should weaken some as they come across the Alleghenies, but that said, strong thunderstorms, drenching downpours and gusty winds are possible overnight in to Wednesday.
Modeled lightning off the HRRR
Rainfall off the HRRR and with these setups, do not focus or pinpoint any particular location. Modeling will not nail these setups with great accuracy, but it’s a great tool for potential rainfall and anyone is fair game to max out or miss out. This runs through midday Wednesday and rain will continue beyond that as well as the intrusion of colder air that will begin to transition rain to snow across the WV High ground Wednesday afternoon/evening and elsewhere overnight.
Temps as we go through the night and beyond off the GFS
That colder air aloft, the 850 temps which are a good indicator of the WV high ground
When you see that gray color, 0° C which is 32°F that a good indicator of the surface temps across the WV High ground and often you’ll see precip transition to snow as that colder air works in. That coldest push later Thursday night, Friday a.m and again Friday pm/ night should be the best snow periods
A look at the precip type off the GFS
Hopefully the GFS beyond the ending of the snow activity Saturday is off for the eclipse time Monday. Other modeling looks a bit better for Monday as far as cloud cover vs the GFS.
No big changes on snow thoughts. Modeling holds fairly steady with typical fluctuations
18z GFS
12z ECMWF
Model Blend
This will give a good idea of ranges but does not take elevation in to account with any detail. Areas below 3000′-3500 will struggle with daytime accumulation and deal with daytime meltback, especially with lulls in the action and compression more so than 4000’+.
So my thoughts on totals and lean low to mid range with these, with a strong performance maxing out. Also keep in mind of the compression and melt as multi day accumulation and snow depths are not the same thing. For example Areas around 2500-3000 may get 3″ Friday morning at 7am, lose a inch or 2 depth midday and pick up 2″ Friday pm and night and may end up with 5-6″ of accumulation, but never have more than 3 or 4 on the ground. As you go up in elevation, temps a notch colder, winds a notch higher and precip consistency a bit more will lead to less daytime melt and compression. And if precip consistency has minimal lulls, that factor becomes less. That’s a product of it being April and the higher sun angle and longer days, warmer ground that can be overcome and we have seen it plenty of times. Even in May.
So the thoughts remain, again, lean low to mid with a good performer maxing out
Notice the snow accumulation angle. As you go east with upslope, you lose some moisture, and also more lulls equal less on the ground, more melting etc when it isn’t snowing. Last May the difference from Backbone Mt to Mt.Storm was significant. Those elevations and west to east thoughts in those images, you can carry that down the Alleghenies PA to Snowshoe/Cranberry Wilderness area. Just some examples of the thoughts on the snowfall.
Rounds of rain, some storms, period of sun more rain
Bittinger 2NW Valley
Dyacon Data Below
Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon “ramps poppin” slightly ahead of schedule Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon “scratch your screen and sniff”Bittinger 2NW Valley 5pm as another round begins Bittinger 2NW Valley evening Bittinger 2NW Valley evening Bittinger 2NW Valley evening Rock Lodge Rd near The Glades evening
Garrett County Airport
Deep Creek Lake morning
Top of Wisp
Afternoon Afternoon Evening
Canaan Heights/Davis 3SE
7am to 7am data mmts coop BP
Climate Reference Network Canaan
Atop Canaan Ski area
–
Cabin Mt at Bald Knob
Cabin Mt-Western Sods
Spruce Knob
Canaan Valley Refuge
Mt.Davis
Snowshoe
Petersburg Grant County Airport
Elkins Airport
Site Comparison
Dy007-Canaan Valley Refuge 3150′, Dy008-Bittinger 2nw Valley 2600′, Dy002-Cabin Mt at Bald Knob 4350′, Dy003-Cabin Mt-Western Sods 4035′, Dy004-Spruce Knob 4820′, Cvpw2-Climate Reference Network Canaan 3380′, KW99-Petersburg Grant County Airport 961, K2G4 Garrett County Airport 2933′, KCBE Cumberland Airport 774′, KEKN Elkins Airport 1985′, KMGW Morgantown Airport 1227′, PMN16-Mt.Davis 3038′, KDCA-Reagan National 15′, G1472 Snowshoe 4500′, F0183 Burkes Garden 3050′
Flood threat, Severe threat, Snow threat remains……
A start with the flood watches that are in effect and have expanded to Somerset County and I’d expect with all the modeling pointing some of the heaviest Pittsburgh to Johnstown you’ll see Cambria fall in to that watch area as well.
Modeling on the rains just past changeover to snow time
18z ECMWF 18z GFS
18z HRRR out 48hrs through 2pm Wednesday
18z HRRR
Rainfall tallies for round 1 plus round 2(Saturday night, Sunday night/Monday am)
Bittinger 2NW Valley 2.08″
Strong and severe storms may accompany the drenching downpours Tuesday in to Wednesday. May area should hold west of the Alleghenies.
So this aspect will need to be monitored as we go through the next 36-48 hours
Then eyes will transition to the backside wintry aspect.
Snow should begin to mix in Wednesday afternoon across the WV high ground first, then elsewhere across the Alleghenies as we go through the overnight Wednesday.
Accumulations initially across the high Wv locations and lowering. Below 3000-3500′ may melt back off Thursday during the peak diurnal afternoon hours and then start accumulating late day. Thursday night through Friday night should be the main accumulation period.
18z GFS
Temps off the 18z GFS
Potential accumulations at elevations below 3000′ again will be impacted by marginal daytime temps, sun angle, so compression and diurnal melt will be most prevalent in this zone. As you go up it will gradually become less and less as temps will be lower and precipitation will be more persistent. There is no diurnal temp rise across the high ground as it’s precipitating. Temps on the tops Friday afternoon may not get out of the mid 20s as the 850 temps suggest.
So upslope snowfall thoughts Wednesday P.M to Saturday A.M
You can carry that same type of thoughts on down the Alleghenies.
The northern Alleghenies with a bit less elevation north will battle that daytime mektback, compression, with the areas near and above 3000′ doing the best.
Modeling looks like
18z GFS12z ECMWF Model Blend
These are not mesoscale models and the grid points are much larger. So, manual judgments of elevation, daytime melt, compression are used. This also will include the snow depth maps some post. Those maps have NO physics for elevational gains over a mile or 2 and more of a blended broadbrush. Those snow depth maps fail throughout the entire winter.
While accumulation and depths over a multi day can vary greatly, that variance is less on the tops vs those lower zones that experience more meltback.
So far things have nearly held course from what modeling showed later last week. So let’s watch to see how the flood risk, severe risk, and that winter threat continue to evolve over the coming days.
Heavy a.m rains near the Mason Dixon, things broke in the afternoon with some sun
Bittinger 2NW Valley
Dyacon Data Below
Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley morning Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon
Garrett County Airport
Deep Creek Lake morning
Top of Wisp
Canaan Heights/Davis 3SE
Climate Reference Network Canaan
Atop Canaan Ski area
Cabin Mt at Bald Knob
Cabin Mt-Western Sods
Spruce Knob
Canaan Valley Refuge
Mt.Davis
Snowshoe
–
Petersburg Grant County Airport
Elkins Airport
Site Comparison
Dy007-Canaan Valley Refuge 3150′, Dy008-Bittinger 2nw Valley 2600′, Dy002-Cabin Mt at Bald Knob 4350′, Dy003-Cabin Mt-Western Sods 4035′, Dy004-Spruce Knob 4820′, Cvpw2-Climate Reference Network Canaan 3380′, KW99-Petersburg Grant County Airport 961, K2G4 Garrett County Airport 2933′, KCBE Cumberland Airport 774′, KEKN Elkins Airport 1985′, KMGW Morgantown Airport 1227′, PMN16-Mt.Davis 3038′, KDCA-Reagan National 15′, G1472 Snowshoe 4500′, F0183 Burkes Garden 3050′
From the start. If you are prone to basement flooding issues with excessive rainfall and need to take preparations. Do so ASAP. If you are in a flood prone area. Take preparation for what’s needed to limit impact.
The Flood watch encompasses the Allegheny Region and the rain will come through in multiple rounds beginning tonight and again Tuesday to Wednesday.
A look at the flood watch
This sould extend in to Southern PA as well.
If 3-5″ of rainfall, even over a 2-3 day period it’s not “could” see flooding. It’s will.
Also the severe threat Tuesday across the area. I think training non severe thunderstorms will be the biggest thing to watch.
A look at the 18z ECMWF (Euro)
Rainfall output off the 18z ECMWF
With this potential why isn’t more of south central PA in the flood watch yet..
And a look at the 18z GFS, less extreme than the ECMWF, but still flooding potential
I stopped the rainfall totals there, not because the precipitation stops, but because that’s when the models begin to transition to snowfall across the high ground.
If you saw yesterday’s post. Not much change to those snow thoughts. A few images for those thoughts
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12z ECMWF
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These models struggle in elevational events, but give a good range of potential. There will be factors that prevent actual totals from say reaching the 27″ output off the GFS. 1-compression during daytime hours. 2- some melting underneath will occur. Ground temps do diddly to get stickage as the upper layer chills rapidly. However once you insulate the ground, then ground temps help melt some underneath.
The core of the coldest and most unstable air comes across Thursday and even a bit more so Friday. Thursday may feature more consistent snow while Friday may see a increased afternoon action with the coldest core of the air overhead and some heavy burst. I know its Sunday, 5 days out. Things can obviously change but these NW flow events often pan out decently as to modeled. Snow lingering until Saturday a.m and the Wv high ground above 3600-4000′ holding below freezing from Wednesday PM through Saturday. Once below that range. More daytime compression, meltback below 3000′. So, more flux in depths vs accumulations there. If some of the better periods occur at night, better accumulation across the board and especially below 3000′ as well that can exceed expectations.
Showers and some storms rolling through. Storms off to the west in eastern Ohio, plenty of lightning with those.
A severe thunderstorm watch with areas west and some areas currently under those have a warning
The watch for those counties runs to 10pm.
The HRRR holds some of those together coming east, so keep a watch on those for mainly downpours
Some showers around Easter Sunday, widely scattered with most of the day just cloudy with temps in the 50s. It’s not until Monday with the next wave of more significant rain and the real deluge is looking like Tuesday with the boundary and focal point of heavy rain running across the Alleghenies.
Let’s look at the 18z GFS
Rainfall amounts from tonight through Wednesday afternoon around the time colder air should get things switched to snow(a bit earlier perhaps across the WV High Ground)
18z GFS total precip amounts in to Wednesday afternoon
12z ECMWF precip total
WPC outlook for excessive rainfall
Day 3
Day 4
With the boundary setup, the threat of storms, some training storms the flood threat is in play and will be monitored as things get closer. Stay tuned to your local NWS for that and I’ll try to post on Facebook or here as we get closer and in that action.
Now, behind it as we go through Wednesday the storms gets off the east coast. NW flow, strong upper low over the lakes and off to the races we go across the high ground.
A very similar overall setup to last May with a bit more cold air availability, being exactly month earlier.
This setup at 500mb
Last May event at 500mb
One more look at the 18z surface outlook
A significant cold air mass for early April. 850 temps during the afternoon running -5 to -6 Thursday and Friday afternoons
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So with it precipitating on this northwest flow, the Wv high ground should remain below freezing above 3700′-4000′ from Wednesday PM to Saturday. Lots of afternoon instability, squalls and steady snow. Even with the high sun angle of April, this is how you accumulate day and or night. Just like we saw last May. Now there will be daytime compression, even where below freezing and blowing snow. The least of these impacts are across the tops where temps remain 20s, snow and strong winds.
The 18z GFS snowfall outlook
And the 12z ECMWF
Some differences as the Euro loses elevation. Keep in mind these are not mesoscale models so it’s a bit of a broad brush and has shortcomings in snowfall maps in elevational dependent events.
My thoughts on a vertical scale
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This is a multi day event. Meaning snowfall accumulations and snowfall depths will not equal. Areas below 3000-3500 will see more compression, some meltbacks and 2500- 3000′, may see melt back more during the day and accumulate at night. The high Wv ground above 3500-4000′, this looks like a prime setup.
I stress, it’s days away. Alterations timing, speed, etc can alter snow amounts. A bit colder air and you can see those higher totals end up a notch lower in elevation. A nice slug comes through at night some of those areas below 3000-3500 can top expectations. So expect tweaks.
Across the tops of all materializes as expected, windblown full on winter look is on the table Wednesday PM to Saturday
These type of winds look likely Wednesday through Friday
Areas of early a.m snow, stickage mainly 2700-2900’+ in spots Garrett, Preston and more widespread stickage in the higher Wv ridges south. High ground fog in Wv. The day the got sunny and winds up the entire day.
Bittinger 2NW Valley
Dyacon Data Below
Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Bittinger 2NW Valley afternoon Rock Lodge Rd evening
Garrett County Airport
Deep Creek Lake morning Deep Creek Lake afternoon Deep Creek Lake afternoon Deep Creek Lake evening
Top of Wisp
Canaan Heights/Davis 3SE
7am to 7am data mmts coop BP
Climate Reference Network Canaan
Atop Canaan Ski area
––––
Cabin Mt at Bald Knob
Cabin Mt-Western Sods
Spruce Knob
–
Canaan Valley Refuge
Mt.Davis
Snowshoe
–––
Petersburg Grant County Airport
Elkins Airport
Site Comparison
Dy007-Canaan Valley Refuge 3150′, Dy008-Bittinger 2nw Valley 2600′, Dy002-Cabin Mt at Bald Knob 4350′, Dy003-Cabin Mt-Western Sods 4035′, Dy004-Spruce Knob 4820′, Cvpw2-Climate Reference Network Canaan 3380′, KW99-Petersburg Grant County Airport 961, K2G4 Garrett County Airport 2933′, KCBE Cumberland Airport 774′, KEKN Elkins Airport 1985′, KMGW Morgantown Airport 1227′, PMN16-Mt.Davis 3038′, KDCA-Reagan National 15′, G1472 Snowshoe 4500′, F0183 Burkes Garden 3050′
Allegheny Mountains Weather 