textproduct: Wakefield

WHAT HAS CHANGED

Confidence increases with respect to the development of a strong coastal low pressure Sunday into Monday. Along with heavy accumulating snow Sunday night into early Monday with the highest confidence across Eastern Va and the Eastern Shore where Winter Storm Watches are in effect.

KEY MESSAGES

1) Cold front continues to push through the area this morning setting across the Carolinas bringing chance of rain showers across the southeast.

2) Strong coastal low pressure expected to impact the region Sunday into early Monday resulting in the potential for heavy accumulating snow, breezy to windy conditions along, the coast and hazardous marine conditions. Winter Storm Watches are in effect for Eastern Va and the Eastern Shore.

3) Minor coastal flooding is possible with the Sunday night/early Monday high tide cycle, particularly along the Atlantic coast.

DISCUSSION

As of 310 AM EST Saturday... KEY MESSAGE 1...Cold front continues to push through the area this morning setting across the Carolinas bringing chance of rain showers across the southeast.

Early morning weather analysis shows moderate to strong WSW zonal flow aloft stretching across the Mid-Atlantic. At the surface, the cold front continues to push through the area this morning and is situated across SE VA/NE NC. Temperatures continue to remain quite mild in places due to a light breeze while places that are experiencing little to no wind have decoupled and temperatures are much cooler. Across the area temps are ranging between the upper 40s to low 50s where the light wind is remaining in place and upper 30s to middle 40s where places have decoupled. Through the rest of the morning and throughout the day a wave of low pressure will track along the stalled out cold front south of the area. This system will help increase cloud cover through the day primarily across the south. In addition there should be enough residual moisture along the front to help bring a chance of rain showers across NE NC. not much QPF is expected as totals will be less than .1". Otherwise, today will be a mild day with highs ranging in the upper 50s to 60F across VA & NC and low 50s across the Eastern Shore.

KEY MESSAGE 2...Strong coastal low pressure expected to impact the region Sunday into early Monday resulting in the potential for heavy accumulating snow, breezy to windy conditions along, the coast and hazardous marine conditions. Winter Storm Watches are in effect for Eastern Va and the Eastern Shore.

Model consensus continues to agree with a strong upper level trough diving out of the Midwest Saturday night and moving into the Mid- South and the Carolinas Sunday, before transferring into a strong closed low off the Mid- Atlantic coast Sunday night. A strong surface low pressure will quickly undertake bomb cyclogenesis Sunday afternoon into Sunday night. Given the event is 36 hrs away there still remains quite a bit of model spread. The latest GEFS and CMC ensembles have the center of the low closer to the coast while the Ecmwf has nudged back to the east. Given there is overall better agreement on a stronger system closer to the coast the Ecmwf looks to be an outlier. Nonetheless, this system is expected to bring heavy wet snow across the northeastern half of the area that will bring hazardous travel conditions and near whiteout conditions primarily across the Eastern Shore. Surface temperatures continue to remain on the marginal side but as this system begins to truly takes form cold air is expected to quickly wrap around leading to snow rapidly accumulating. Across Eastern VA snow totals have risen and from the southern peninsula stretching up towards the Northern Neck snow totals are expected to range between 2 to 4" with possibility of isolated higher totals as some models have hinted on better banding across the area. While across the Eastern Shore confidence is extremely high for much higher snow totals and near white out conditions along the coastline. All model guidance continues to hint on strong banding and heavy rates nearing 2" hr. Snow fall totals for MD are expected to be between 6 to 9" with higher totals possible while across the VA Eastern Shore 3 to 5"+ are expected. In addition, as the low begins to rapidly deepen the pressure gradient will tighten allowing for breezy and windy conditions across the area. Across Eastern Va wind gusts could be as high as 35+ mph. While across the Eastern Shore wind gusts are expected to be near 40-50+mph especially along the coastline. This will bring near white out conditions and perhaps brief Blizzard conditions. If trends continue on a stronger system Blizzard Warnings will perhaps be needed along the MD Eastern Shore Coastline. The overall confidence for heavy wet accumulating snow hazardous travel conditions is high across these areas. Therefore a Winter Storm Watch has been issued. While elsewhere snow totals are expected to remain low and most places may see a dusting to 1-2". Additional winter headlines maybe needed at a later time.

Temperatures will be below average to begin the week, with a moderating trend by midweek ahead of another cold front. There is a chance of rain with this cold front later next week.

KEY MESSAGE 3...Minor coastal flooding is possible with the Sunday night/early Monday high tide cycle along the Atlantic coast.

Strong onshore flow is expected on Sunday as low pressure strengthens offshore. As a result, tidal anomalies are expected to rise, especially along the Atlantic coast and particularly across the northern Eastern Shore which will be closest to the strong low. Ocean City has the potential to see high-end minor tidal flooding with the Sunday night/early Monday morning high tide. Down the coast, minor flooding is also possible at Chincoteague. Tides remain elevated through Monday before gradually diminishing early next week.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

As of 125 PM EST Saturday...

VFR conditions prevail through the rest of the afternoon and evening. NE winds mainly 5-10 kt this afternoon, becoming light and variable this evening and tonight. Maintained a mention of rain at ECG through the afternoon but radar shows mainly light returns so not expecting any restrictions. Conditions go down hill late tonight with MVFR CIGs and VSBY impacting all terminals by 12z Sunday. IFR CIGs will then quickly move in across the region as low pressure develops S of the area. NE winds also begin to increase but the main period of strong winds is just outside the 18z TAF period.

Outlook: Strong low pressure develops off the coast Sunday into Monday with the potential to bring another period of rain changing to snow, gusty winds, and flight restrictions to the region Sunday into early Monday. Expect LIFR or VLIFR conditions in snow or blowing snow for SBY late Sunday night into Monday. Remaining breezy on Monday as drier air and high pressure filter into the region with a return to VFR conditions later Monday.

MARINE

As of 300 AM EST Saturday...

Key Messages:

- Sub-Small Craft Advisory conditions are expected through tonight and into early Sunday morning.

- A strong system impacts the waters later Sunday into Monday. Storm Watches have been issued for the northern coastal waters with Gale Watches elsewhere.

Early this morning, a cold front has crossed the waters, turning the winds to the NW ~5-10 kt. Sub-Advisory conditions are expected through today and into early Sunday morning as weak high pressure briefly builds across the area. Winds become NE and increase to 10- 15 kt later Sunday morning ahead of the next, stronger system.

Dangerous marine conditions are expected later Sunday and especially Sunday night/early Monday morning as a strong low pressure system develops near the coast Sunday and moves out to sea. The low will likely deepen to 975-980mb by Monday. However, how quickly (and close to the coast) it deepens will determine exact impacts to our marine area (but degraded marine conditions are likely regardless). There are still some differences in the models and their respective ensembles, but the 00z/21 guidance has trended slightly towards a stronger system closer to the coast. The GFS/NAM remain the strongest and closest to the coast, but the ECMWF and Canadian have both continued to trend upward with respect to winds. The current forecast shows winds becoming N at 20-25 kt (w/ gusts to 30 kt) by Sunday afternoon before becoming NW Sunday night and increasing to 25-35 kt with gusts to 35-45 kt. Across the northern coastal waters, winds increase to 30-40 kt with gusts of 50+ kt possible. Peak winds are expected to occur between midnight and 9 AM Monday before diminishing to 20-25 kt with gusts to 30 kt Monday afternoon (with the wind direction remaining NW). Regardless of specific model details, local wind probabilities for 34+ knot wind gusts are now 70- 90+% over much of the waters. In addition, local wind probabilities for 48+ knot wind gusts have increased significantly, especially over the northern coastal waters where they show 50-70%. Given all the above, have issued Storm Watches for the coastal waters north of Cape Charles Light Sunday evening-Monday afternoon. Gale Watches have also been expanded to include the tidal rivers. SCA winds are expected to continue through much of Tuesday morning before finally dropping below SCA levels during the day on Tuesday as high pressure returns to the area. Calmer conditions later Tuesday through the first half of Wednesday before a round of (marginal) SCA conditions is possible later Wednesday through Thursday.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Winter Storm Watch from Sunday morning through Monday evening for MDZ021>025. NC...None. VA...Winter Storm Watch from Sunday morning through Monday evening for VAZ075>078-083>086-090-099-100-517>523. MARINE...Gale Warning from 6 PM Sunday to 1 PM EST Monday for ANZ630>638-656-658. Storm Warning from 6 PM Sunday to 1 PM EST Monday for ANZ650- 652-654.