textproduct: Wakefield

WHAT HAS CHANGED

Severe weather continues ahead of a strong cold front today. The Storm Prediction Center has maintained a Moderate Risk (level 4/5) with probabilities to 60% for wind and 10% for tornadoes across much of the area.

KEY MESSAGES

1) Showers and storms continue this afternoon and this evening. SPC has maintained the Moderate Risk(level 4/5) for western and central portions of the area with an Enhanced Risk (level 3/5) in place for the rest of the area (except eastern portions of the Eastern Shore with a Slight Risk).

2) Cold and breezy Tuesday, with a hard freeze likely for most of the area Tuesday night/early Wed morning. It remains dry, with seasonable temperatures returning late in the week.

DISCUSSION

As of 320 PM EDT Monday...

KEY MESSAGE 1...Showers and storms continue this afternoon and this evening. SPC has maintained the Moderate Risk(level 4/5) for western and central portions of the area with an Enhanced Risk (level 3/5) in place for the rest of the area (except eastern portions of the Eastern Shore with a Slight Risk).

The severe threat continues this afternoon, though the first part of the event has proved underwhelming. This is due to the messiness of the pre-frontal activity that moved through this morning. A few spin ups have been observed, with one tornado warning issued for parts of NE NC near Edenton, as well as more recent one issued for near Elizabeth City. The environmental conditions continue to remain favorable for severe weather, especially in NE NC and SE VA where the most healthy line of convection moving through. There is a tongue of MLCAPE extends across that area which has helped increase the severe potential. The special 18Z sounding KMHX showed a very supportive environment, with ~340 m2/s2 0-1km SRH and MUCAPE of almost 1900 J/kg. Farther north across the local area, a similar, yet slightly less favorable environment is likely occuring due to temperatures and dew points being a little lower with limited clearing. While lots of shear and moisture remain in place, the limiting factor remains instability and the fact the environment has been worked over from previous, non-severe morning convection. SPC sent an updated outlook that did drop the tornado probs across the region, but the higher wind probs remained the same as the strong upper jet continues to move across the area. While less coverage of severe has been realized so far, the multiple rounds of thunderstorms is going as expected. The SE portion of our will continue to see storms moving through for the next few hours ahead of the front. Hi-res guidance continues to bring the front through our area from west to east between the hours of 7-10 pm (plus or minus an hour pending the exact development of this line). This line will bring one last punch of wind as it will be racing across the local area rapidly. Strong to severe winds are expected along this line and a few tornadoes along the line cannot be ruled out. While some may think that the event is over, it is important to remain weather aware until after this front comes through and not to find yourself caught off guard.

KEY MESSAGE 2...Cold and breezy Tuesday, with a hard freeze likely for most of the area Tuesday night/early Wed morning. It remains dry, with seasonable temperatures returning late in the week.

Solid pressure rises are expected behind the front, which will keep breezy conditions through Tuesday afternoon with gusts of 20-25 mph possible. A very cold airmass will move in behind the front, bringing temperatures down below normal on Tuesday and Wednesday, with highs only reaching the 40s. Most of the area can expect a hard freeze on Tuesday night/Wednesday morning as high pressure builds in overhead and winds trend downwards. Lows will drop into the upper 20s to lower 30s, with the exception being the NC OBX, where temperatures will be a little more modified by the surrounding bodies of water. Temperatures will start to trend warmer by late week, with generally dry conditions currently forecast through the weekend.

AVIATION /19Z MONDAY THROUGH SATURDAY/

As of 205 PM EDT Monday...

There is currently a mixed bag of flight conditions across the forecast area. Both ORF and PHF are seeing heavy thunderstorms, SBY is only observing -RA, and ECG and RIC are currently in a convective lull. Today's thunderstorms are fast moving, so flight conditions have been changing rapidly. Generally sub-VFR conditions will continue through early tonight until after the cold front gives the terminals one last punch of wind/rain. Have included PROB30 at all terminals (roughly between 01-04z) to try and capture this line as it moves through the terminals, though this could change if things speed up or slow down. LLWS is currently impacting the terminals as a LLJ moves across the area. This LLWS will linger through around 02- 03z before finally tapering off. Surface winds have been under performing somewhat, but an increase in winds is still expected as the afternoon wears on. In the wake of the front, conditions will start to improve and winds will start to decrease, though they will remain gusty at 20-25 kts through the morning.

Outlook: Dry/VFR conditions return Tue on breezy WNW winds, remaining dry Wed-Thu with diminishing winds.

MARINE

As of 245 PM EDT Monday...

Key Messages:

- A strong cold front will cross the local waters this evening. Small Craft Advisory conditions continue in advance of the front, with a period of gale conditions expected late this afternoon and evening.

- A few strong to severe thunderstorms will be possible across the waters through this evening. The main threat is strong wind gusts to 55kt along with the potential for a few waterspouts.

As low pressure deepens and lifts NE through the Great Lakes this afternoon, a strong cold front will approach from the W, then cross the Mid-Atlantic coast later this evening into the early overnight hours. Modestly strong pressure falls, a tight pressure gradient, and a 65-80 kt LLJ favor a 3-6hr period of southerly gales, primarily for the northern coastal waters, but a ~3hr period of gale conditions is also likely for the southern coastal waters, Ches. Bay, lower James, and Currituck Sound late this aftn and evening. Occasional gusts to 35kt are also possible over the upper rivers, but periodic showers/tstms through the evening are likely to disrupt the synoptic flow for the marine zones farther inland. Stable low-level lapse rates with a mild and moist airmass overspreading cold ocean water will be a limiting factor for anything more than just a few strong to locally severe storms through this evening. Local wind probs still depict the 70-100% probs of 34kt gusts over most of the marine area with the exception of the upper rivers, and even a 30-50% chc of 43kt gusts N of Parramore Is. Sharp pressure rises of 10-12mb/3hr will result in strong WNW wind gusts along and immediately behind the cold front, which could also be enhanced by any convection. Seas build to 7-9ft S to 9-13ft N, with waves in the Ches. Bay of 3-5ft, and 5-7ft at the mouth of the Bay. SCAs remain in effect through late morning/early afternoon, with Gale Warnings going into effect late morning through the afternoon and continuing through 1 AM. The Currituck Sound also remains in a Gale Warning.

Remaining breezy Tuesday, with a secondary surge possible for the Ches. Bay and coastal waters Tuesday night. This may allow for SCA conditions to continue, or resume for the Ches. Bay. Meanwhile, seas will be slow to subside Tuesday into Tuesday night. Otherwise, more benign marine conditions are expected by mid to late this week as high pressure settles across the region.

AKQ WATCHES/WARNINGS/ADVISORIES

MD...Wind Advisory until 1 AM EDT Tuesday for MDZ021>025. NC...Wind Advisory until midnight EDT tonight for NCZ015>017-032- 102. VA...Wind Advisory until 1 AM EDT Tuesday for VAZ099-100. Wind Advisory until midnight EDT tonight for VAZ095-097-098. MARINE...Gale Warning until 1 AM EDT Tuesday for ANZ630>632-634-638-650- 652-654-656-658. Small Craft Advisory until 4 PM EDT this afternoon for ANZ633. Gale Warning until 1 AM EDT Tuesday for ANZ633. Small Craft Advisory until 6 AM EDT Tuesday for ANZ635>637.