Excessive Heat Watches are being issued and the map below will see those expand. By later today you’ll likely see the red highlighted area blossom as more counties fall under the criteria. As of now
As we go from today to Monday, 2 things will be noticeable.
1- Temps will be warmer
2- Dewpoints will be up
This combo will lead to some stationary to slow moving showers and short lived storms in areas. Not widespread, but it’s a setup isolated areas develop and rain out near the area they developed.
Temps this week off the 0z GFS
Dewpoints off the 0z GFS
Relative Humidity
If there is a saving grace this week, under the big dominating ridge that centers overhead, afternoon peak heating times after Tuesday occur with dewpoints that are in the modest zone. So in a little respect, those days, the worst of the heat is a relatively “dry heat” for peak afternoon heating. However, dry air does heat up a easier vs moist air. The less water molecules in the air that heat up much slower than air, the more rapidly the air temp increases with incoming solar radiation. Hotter ambient air temp though does not always feel hotter though and the drier air allows our body to have some evaporative cooling as we sweat. Hence the saying “but it’s a dry heat”.
From Wednesday in to the weekend, we should see Valley areas still falling off in to the 50s at night and potentially even a upper 40 or 2 late week in the coldest spots. Dewpoints will rise a bit overnights and dry out some in the afternoon. As temps, dewpoints grow closer at night, the air is more saturated so naturally on the modeling you see the relative humidity increase.
Temps across the high ground this week look to run mainly 80s. You’ll have the highest Wv locations run 77-82, in towns 86-91 with most areas falling those in between across Alleghenies.
The lower elevations for example Cumberland, Morgantown, Petersburg, etc etc will take runs in the mid to upper 90s and I suspect you’ll see some UHI (urban hear island) effects pushing in town temps over 100-105°.
Weather Service Numbers
K2G4 Garrett County Airport
KCBE Cumberland Regional Airport
KGMW Morgantown
KEKN Jennings Randolph Field Elkins
Across the high ground afternoon Heat Indexes will not be much different than the actual ambient air temperature from mid to late week. They will run a bit higher Monday/Tuesday
Heat Index Charts below using RH and DP
In Review
- Muggiest weather of the work week is Monday, Tuesday
- Hot all week
- Localized slow moving to stationary showers and storms Monday and Tuesday. Those can form and rain themselves out without a great deal of movement. They will also aid in the muggy and temporarily oppressive feel once over.
Things to expect
- In town temps to run hotter
- Low elevations in town UHI areas to exceed 100° at least once
- Spruce Knob to crack 80°
If you’re working outside, use some caution if you have any of the following symptoms
Stay tuned to your local NWS as heat watches expand. https://www.spc.noaa.gov/products/wwa/
In general just expect it to be a hot week.
Also remember you can use your point and click options on the weather service maps
https://forecast.weather.gov/MapClick.php?x=255&y=200&site=pbz&zmx=&zmy=&map_x=254&map_y=200
Click the map for your location
Then click on the graph option on the site for your area
(these will not forecast night valley temps well)
Again many bogus temperature numbers will be reported this week. Reliable accurate temperatures will rely heavily on a well sited station (6 foot, good air flow away from heat impacting objects) and proper radiation shield. Shaded roof eaves, shaded trees still will trap heat radiation leaving numbers higher than reality. Rooftop stations will struggle. Car thermometers impacted by their surrounding heat source and pavement. Those will come in line somewhat better as you get traveling, but still are getting surface warmth in the area you’re driving.
examples of good radiation shields
when properly sited these will aid the sensor in a more accurate reading. With calm to light winds, even these can be impacted some during high solar periods and a mechanically aspirated shield would be slightly better.
Bank thermometers are not an example of a proper site. You’ll notice many business, bank, police barrack thermometers, the sensor is either close to the surface or the surface of a heat absorbing object. Greatly impacting the number shown.
Just a grass surface will run much hotter than at 6ft the standard height of recording
and pavement much hotter
Easy also to see why those objects impact temp readings if the sensor is too close.
Stay Cool…
And think cold
Allegheny Mountains Weather 