textproduct: Wakefield

WHAT HAS CHANGED

Wind chills tonight have trended a bit warmer and will fall shy of Cold Weather Advisory criteria. Chances for snow and very cold temps have continued to increase this weekend, though uncertainties remain regarding coverage, timing, and precip type.

KEY MESSAGES

1) Cold and dry weather prevails through Wednesday, with Tuesday being the coldest day. Temperatures potentially moderate some Thursday.

2) Chances for impactful winter weather are increasing this weekend. Exact details remain unclear at this time, but users should keep a close eye on the forecast this week.

DISCUSSION

As of 220 AM EST Monday...

KEY MESSAGE 1...Cold and dry weather prevails through Wednesday, with Tuesday being the coldest day. Temperatures potentially moderate some Thursday.

A deep-layer trough will remain situated over the eastern CONUS through Tuesday. At the surface, Arctic high pressure gradually builds down from the northern Plains into the MS Valley, eventually settling over the area Wednesday. Seasonable to slightly below- normal temperatures are expected today in the wake of yesterday's system. Dry wx and sunny skies are also expected as drier air filters in. A reinforcing cold front pushes through tonight, with additional cold advection overspreading the region. The coldest temperatures of the week are then expected Tuesday as another trough slides through and 850 mb temps bottom out around -15 C. Lows Tuesday morning drop into the mid-upper teens for most of our CWA, with lower 20s in coastal SE VA and NE NC. With a light NW wind, wind chills are progged to drop to 10-20 F for most of the area, with 5-10 F possible in the Piedmont on the MD Eastern Shore. Highs Tuesday may struggle to get above freezing in these spots as well. Elsewhere, highs will still only be in the mid-upper 30s. Very cold again Tuesday night with lows again in the teens. However, there shouldn't be much wind to lower the wind chills below the air temp.

The upper flow turns more zonal for the middle of the week. This should allow temps to moderate into the 40s Wednesday and then 50s by Thursday. A series of weak cold fronts will move through Wednesday night and again Thursday night. While these will be mainly dry (as the best forcing remains N and NW of us), cannot completely rule out a light rain or snow shower Thursday morning. PoPs are generally 20% or less. Cooler temps return for Friday behind these fronts.

KEY MESSAGE 2...Chances for impactful winter weather are increasing this weekend. Exact details remain unclear at this time, but users should keep a close eye on the forecast this week.

There remains an impressive medium range signal for impactful winter wx this upcoming weekend, potentially starting as early as Saturday morning. However, it must be stressed that uncertainties remain regarding the exact precipitation evolution. Details below.

The EPS/GEFS continue to depict a highly anomalous trough and upper low diving into the northern CONUS late this week. Meanwhile, a very strong Arctic high pressure system is expected to build southward into central CONUS and Great Lakes region by Friday. Ensemble means from the EPS and GEFS suggest the high builds to at least 1045 mb, with several deterministic runs and individual ensemble members in excess of 1050 mb. This will provide an ample and rich supply of cold air for any moisture to work with, unlike yesterday's system which lacked any preexisting cold airmass. Regarding moisture, the upper pattern appears quite favorable for an active storm track and a significant winter event, with a strong Alaskan ridge, an active/amplified southern stream over the S/SW CONUS, and the aforementioned troughing to our N. There is increasing agreement among most model guidance and ensembles on an expansive precip shield blossoming in the southern Plains and over Texas on Friday, expanding ENE into the Deep South and TN Valley by Saturday as a strong subtropical jet expands NE and strengthens. This precip will overrun the very cold airmass, likely leading to a large area of winter precip across the central and southern CONUS. For us locally, there remains several uncertainties that will determine what we see exactly. The depth of the cold air will be critical in determining snow vs freezing rain. A stronger/more dominant high would also favor a suppressed system with the highest wintry precip chances for the southern half of the area. On the other hand, a further N storm track would places these higher amounts across our N, which also increases the probs for mid-level warm advection and freezing rain or sleet. Such a scenario is hinted at by the 00z UKMET. For simplicity's sake, will the wx-type forecast limited to rain and snow at this range.

Snow probs from all modeling systems, including the AI ensembles and NBM, are very impressive for an event that's still ~6 days out with 50+% probs for >3", 30+% probs for >6", and 10+% probs for >12". There are also probs for freezing rain, though these are highest from the NC/VA border and points S. These amounts are likely to waver back and forth some over the next few days as the finer details become clearer. In summary, there is increasing confidence in a widespread winter wx event for our area which could bring significant impacts. Exact details regarding precip timing, coverage, and type remain uncertain and should be resolved over the next few days. Stay tuned!

Wintry precip aside, there is high confidence in very cold air spilling into the region for the weekend into early next week. Could certainly see widespread low temperature readings in the teens and even single digits, with daytime highs Sat and Sun potentially only in the 20s and 30s. Should any snow cover be present, these temps would likely be even lower.

AVIATION /07Z MONDAY THROUGH FRIDAY/

As of 1225 AM EST Monday...

Lingering MVFR at ECG will improve to VFR over the next few hours. Otherwise, any residual clouds will continue to clear this morning. SKC conditions prevail later today into tonight with gusty WSW winds (to 20 kt) developing this afternoon. Winds shift back to the NW tonight as a secondary (dry) cold front drops through.

Outlook: Dry/VFR Monday morning through Wednesday. A cold front potentially crosses the area Thursday with only a 20% chance of showers at this time. Low-end precip chances continue into Friday.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...Small Craft Advisory from 10 AM this morning to 4 AM EST Tuesday for ANZ630. Small Craft Advisory from 1 PM this afternoon to 4 AM EST Tuesday for ANZ631-632-634-650-652-654. Small Craft Advisory from 1 PM this afternoon to 1 AM EST Tuesday for ANZ633-656-658. Small Craft Advisory from 1 PM this afternoon to 7 PM EST this evening for ANZ638. Small Craft Advisory until 4 AM EST early this morning for ANZ650-652.