Cool & Damp Conditions Linger Through The Monday Morning Commute...Before A Warm Start To December...
Good Sunday to you! Well...I think we can sum today up as a cool and damp one. While the rain certainly wasn't heavy this late-morning and afternoon...it was persistent in the form of some drizzle. There was only a one to two hour 'break' in the action this afternoon in Charleston, before additional pockets of drizzle developed underneath a thick shield of low, stratus clouds. As a result of the low clouds and some drizzle at times...afternoon high temperatures only reached the upper 40s to around 50 degrees. Not exactly balmy...but it could be a lot worse this time of the year! How long will this wet weather pattern continue? Does December look to start unusually warm? Some snow flurries eventually in the forecast? How does your weekend look? Here is your complete and detailed, seven-day forecast...
THIS EVENING: Cloudy and cool with pockets of drizzle. Rain showers increasing in a south to north fashion and nearing I-64 by 10-11 PM. Temperatures staying steady in the mid to upper 40s.
*Thanks to a temperature inversion (warmer air aloft)...low, thick, stratus clouds will be the rule this evening. Underneath those low clouds...pockets of drizzle will occasionally occur from I-64 and north.
*Due to these clouds...temperatures will stay pretty steady in the mid to upper 40s. It will be cooler across the northern counties in the lower 40s and milder across southern West Virginia...mostly around 50 degrees there.
*Further south, across southern West Virginia and southeastern Kentucky, a warm-front will begin to inch back towards the north. This surge of moisture is already allowing for a widespread band of light to moderate rain to occur towards our south...and it will get closer to the I-64 corridor by 10-11 PM.
*Roads are still damp across much of the region...so be careful if traveling. Spray and a glare can sometimes make for poor visibility.
*Given the high moisture content of the air in the lower atmosphere...low clouds and fog will be around, especially on the hilltops and ridges.
*The heaviest rainfall this evening will occur across far southern WV, far southeast Kentucky and southwestern Virginia...that's where the deepest moisture exists. That's also where a stronger, upper-level disturbance will ride along/near the surface warm-front.
TONIGHT: Cloudy and fairly mild with increasing rain showers as the night goes on, especially from US Route 33 and south. Some areas of low clouds and fog. Low: 45.
*Expecting widespread rain showers to inch towards I-64 and north around Midnight, or shortly thereafter, thanks to a warm-front lifting this way.
*Most of the rain should stay from Route 33 (Jackson, Mason, etc) and south...as the best moisture and upper-level energy stays mostly south.
*Watch for wet roads and poor driving conditions as the night goes on.
*The heaviest rain, thanks to deeper moisture and a strong, upper-air disturbance or two, will occur across southern West Virginia and southeast Kentucky.
*Most areas between Charleston and Huntington should receive about 0.3-0.4" of rain overnight. Far southern counties may see as much as 0.6 to 1.0" of rain...but not enough to cause water concerns.
*With the relative humidity high in the lower atmosphere...expecting low clouds and some areas of fog again tonight, especially along the ridge-lines.
*With the low-level winds veering more out of the east late...it will turn cooler and breezy across the eastern mountains thanks to an upslope effect there. Still...the atmosphere doesn't look cold enough to produce anything but a chilly rain. The only small exception would possibly be across the far northeastern counties near the Virginia state line, where a touch of freezing rain/sleet may occur in the deepest and most-secluded valleys.
*Temperatures may rise a degree or two late, especially on the hilltops, as the low-level winds shift more out of the east (downsloping for areas west of the mountains).
*Where's the cold air? The bottomline...without the northern Jet Stream being involved (well north into Canada), the cold air is staying locked up. The colder air across the Central United States the past few days has turned stale and has moderated.
MONDAY: Mostly cloudy and mild with rain showers, especially during the morning. Rain turning more scattered in nature during the mid to late-afternoon. High: 58.
*Last day of November! Where does time go!?
*With the warm-front lifting back towards the north, along with some upper-air disturbances moving overhead, expecting fairly widespread rain showers to start the day. Be prepared for wet roads for the morning commute.
*Low clouds and some fog will also be around...especially on the hill-tops and ridges.
*In response to a developing low-pressure over the Midwest...our winds will shift more out of the southeast. This downsloping flow will dry the low-level air out a bit in the afternoon west of the mountains...so expecting the shower activity to become more scattered/broken-up in nature. This means some dry time in the afternoon.
*Likewise, this southeasterly wind-flow will be an 'upslope wind' for the eastern, mountain counties...so expecting chilly temperatures in the 40s there with low clouds all day.
*Mostly cloudy skies will be the rule. However, it's not entirely out of the realm of possibility, given the downsloping flow, that a faint peek of sun or two may try to briefly come out during the afternoon. This would especially be true just west of the higher terrain (I-79, US Route 119 Corridor). If this happens, then temperatures may turn a degree or two warmer.
*With a low-level jet (fast ribbon of winds a few thousand feet off the ground) nosing into the southern counties...along with the downsloping effect taking shape, expecting the most concentrated rain to occur across Southeast Kentucky and southern West Virginia.
*Due to a touch of elevated instability suggested by the short-run models, and the low-level jet axis nearby...a rumble of thunder may occur across parts of southeast Kentucky and far southern West Virginia, but not expecting any severe weather.
*With a southeasterly, downsloping flow increasing as the parent low-pressure develops in the Midwest...wind-gusts of 15-25 mph will become common in the afternoon along the ridge-lines. This especially looks true along US Route 19 and east.
MONDAY NIGHT: Mostly cloudy and mild with increasing rain showers from the south as the night goes on. A rumble of thunder or two possible. Low: 49.
*Like Sunday Night...expecting widespread rain to increase from the south here, too.
*Widespread showers and possibly even a rumble of thunder or two (due to some elevated instability) will increase as a result of a low-level jet (fast ribbon of winds about 5,000 feet OFF the ground) nosing into the region. This feature will be associated with a parent low-pressure strengthening across Minnesota and Wisconsin overnight.
*Some of the rain may turn a little heavier, especially across eastern and western counties...where the effects of downsloping are a little lesser.
*This activity will also be directly associated with the surge of warmth and moisture (theta-e surge, main warm-front, etc) out ahead of a developing cold-front...and some upper-air disturbances moving overhead in the southwesterly wind-flow aloft.
*Due to this faster wind-flow aloft (low-level jet axis)...some gusty winds (20-30 mph) may occur across the higher elevations and ridges. The low spots most likely won't see breezy conditions, as the rain-cooled air keeps the stronger wind energy 'locked up' aloft.
TUESDAY, DECEMBER 1ST: Mostly cloudy and warm with widespread rain, especially early in the day. Rain turning more scattered in nature with even a thunderstorm or two possible during the afternoon. High: 67.
*The First Day of December!
*Strong lift (rising air motions) associated with the low-level jet axis and some upper-air disturbances riding up from the southwest will allow for widespread, and potentially heavy, rain for some to start the day. This especially looks true across western counties...where the drying effects of downsloping tend to be lesser.
*With deep moisture and even some elevated instability (air that's unstable up above)...a few rumbles of thunder may also be around to start the day.
*Road conditions don't look great for the Tuesday morning commute. Widespread ponding of water will most likely occur...so allow yourself extra time; the risk for hydro-planing will be elevated and the visibility from the spray/glare will be poor for most locations.
*Expecting the rain to turn more scattered/broken-up in nature during the 2nd half of the day (sound familiar?), as the LLJ axis moves away and a downsloping, southerly breeze increases.
*A few peeks of sun, given a downsloping wind, may briefly and faintly emerge in the afternoon. This especially looks true west of the higher terrain and closer to the I-64 corridor.
*Decided to go higher on temperatures given breaks in the rainfall and a downsloping breeze in the afternoon out ahead of a cold-front.
*It looks like the front will near from the west by the late-afternoon/early evening...so expecting a broken line of showers/possible thunderstorm then. Winds will also turn gusty in the 20-30 mph range.
*Despite the strong wind-shear aloft...not too concerned with a Severe Thunderstorm Risk at this point, as the overall instability and upper-level support right along the front looks marginal. However, given the fast flow aloft...will watch it carefully.
WEDNESDAY: Partly sunny, cooler and brisk. A scattered rain and/or snow shower possible late in the day, especially across western and northern counties. High: 55, but falling into the 40s late.
*Some rain showers look to persist early on across the eastern, mountain counties...as the front slowly moves towards Virginia and Maryland.
*There won't be a huge punch of chilly air initially...as the parent trough and cold pocket of air aloft lags back towards the west early on.
*With drier air wrapping in around the parent low...expecting a little bit of sunshine early in the day with breezy conditions.
*High temperatures should reach the mid 50s by the afternoon...before widespread stratocumulus clouds begin to develop in advance of a vigorous, upper-air trough.
*This upper-air trough, along with a cool and moist, west-northwesterly flow in the lower atmosphere, will try to initiate some pop-up showers by the late-afternoon and evening. This especially looks true across western and northern counties. Most of this day looks dry, though.
*Given colder air, both at the surface and aloft, moving in from the west-northwest by evening...some of these showers (convective in nature due to a little bit of unstable air) may produce a rain/snow mix, especially north and also east into the Mountains.
*Wednesday Night into Thursday Morning...some upslope flurries and snow showers are likely, especially for the mountains, as chilly, moist, northwesterly flow takes shape. A few flakes may fly across the lowlands, too...but not expecting anything significant.
THURSDAY: Partly sunny, chilly and brisk with a few flurries and/or a snow shower, especially early and east into the mountains. High: 44.
*Not expecting any accumulations for the lower elevations...but a half inch or so of snow may accumulate from US Route 19 and east into the Mountains early on.
*With a slight breeze...it will feel even chillier at times in the 30s. Good jacket weather!
*Given a chilly, moist, northwesterly flow around the eastern periphery of a high-pressure in the lower Ohio Valley...expecting some low clouds and flurries to be generated here by the upslope effect (when the air is forced up the mountain slopes...anytime air rises it cools and can produce precipitation). This especially looks true across the eastern, mountain counties...where the lift is a little stronger thanks to steeper terrain.
*A few flakes should fly across the lower elevations, too...especially early on, but nothing significant.
*By the mid-afternoon...the stratocumulus clouds, generated by the upslope effect, should break down in a west to east-fashion. The best moisture in the lower atmosphere should move off towards our east and erode by then.
*Expecting a cold night into Friday morning...as a high-pressure builds into the region. With mostly clear skies, light winds and low dewpoints (dry air)...temperatures should fall into the mid to upper 20s.
FRIDAY: After a cold start, sunny, dry and cool in the afternoon. High: 52.
*Expecting a cold start in the mid to upper 20s here.
*However, given a very dry atmospheric column...which will allow for bright blue skies and sunshine, temperatures will recover nicely in the afternoon.
*With a high-pressure nearby...winds will be very light, so thankfully that won't make it feel any cooler in the afternoon.
*One of the older runs of the ECMWF model was suggesting a secondary trough moving down from the northwest here...which would allow for some clouds. However, that model run appears to be a one hit wonder...and doesn't show that scenario anymore. Based on this, along with other models suggesting a high-pressure nearby, the sunny solution makes the most sense!
*Will turn cold quickly after sundown thanks to the dry air in place...so have a heavy jacket with you if you're out and about on Friday night.
SATURDAY: Mostly sunny, dry and mild. High: 60.
*Another cold start early in the morning here...most places will start in the upper 20s to around 30 degrees.
*However, with the high-pressure moving into the Northeastern United States...expecting an even nicer warm-up in the afternoon, as the low-level winds shift more out of the east-southeast (slight downsloping flow).
*With a dry atmosphere in place...expecting plenty of sunshine! This sunshine, along with an east-southeasterly flow, will push temperatures to about 60 degrees!
*Only expecting some high, wispy, cirrus clouds at best here...otherwise, a lot of sun!
*Who said you can't play Golf in December!? ;)
SUNDAY: Partly cloudy, dry and mild with a slight breeze. High: 63.
*Models show the high-pressure moving off the Mid-Atlantic coast here...which will allow for a mild and quiet day!
*With a dry and stable atmosphere in place...it looks like another quiet day!
*The Northern Jet-Stream will still be well towards the north here...so cold, Arctic airmasses will stay locked up in Canada.
*A slight breeze looks to develop in the afternoon along the western periphery of the high-pressure.
*Some high, wispy, cirrus clouds will move up from the southwest and thicken some...but that's it!
Have a great night and take care!
WCHS Meteorologist, Brandon Stover