Marine Weather and Tide Forecast for Irvington, VA

KEY MESSAGES
1) A cold front brings a chance for showers and possibly a rumble of thunder late today through early tomorrow morning.

2) Cool Thursday, then warming up to above average temps for the weekend into the middle of next week.

DISCUSSION
As of 225 PM EDT Wednesday...

KEY MESSAGE 1....A cold front brings a chance for showers and possibly a rumble of thunder late today through early tomorrow morning.

Low pressure across the northern Great Lakes region is dragging a cold front across the Ohio River Valley this afternoon, with some convection popping up along it. Currently, a very dry airmass with RH values in the upper 30s to lower 40s. Some cu is popping up mainly in the SE, but no showers are noted due to the dry air in place. The dry airmass combined with temperatures in the 70s is making for quite a pleasant day. High pressure in the Atlantic still extends across the area, producing SW flow. The tightened gradient between the high to our east and the low to our NW has led to gusty winds, with the highest gusts of upwards of 30 mph being measured across the Eastern Shore.

The aforementioned front will advance towards the forecast area this afternoon, moving through late today and into tonight. Hi-res guidance continues to show meager rainfall accumulations associated with the frontal passage, with very limited potential for any thunder. Though the best dynamics for any convection remain just outside of our area at this time, a deep trough aloft should hopefully be enough for at least some rainfall across most of the area, with amounts of 0.1-0.25" confined to the northern half of the area. Areas across southern VA and NE NC will be lucky to see anything over 0.01" today, as this system has attempted to dry that area out completely. Of note, a some models continue show a brief uptick in precip chances around daybreak Thursday across the SE (associated with the shortwave pushing through), but confidence in this precise scenario is low so PoPs will only be 20-30% Thursday morning in the SE. Marginal instability will be available so an isolated thunderstorm cannot be ruled out if these showers do develop. Lows overnight into Thursday will range from the upper 40s/around 50F NW to the upper 50s SE. Though any rainfall is helpful, this meager amount of possible QPF will not even scratch the surface of the current rainfall deficit the entire area is in.

KEY MESSAGE 2...Cool Thursday, then warming up to above average temps for the weekend into the middle of next week.

Temperatures remain cool Thursday, as the upper low becomes centered over the NE and mid-Atlantic region. Highs Thursday will be about 5- 10 degrees below normal, generally in the upper 60s to lower 70s.
Expect variable cloudiness, with some uptick in aftn cloud cover likely due to daytime heating from the strong May sun angle. Would not be surprised to see a few sprinkles or isolated showers redevelop in the aftn. For now, the models seem to focus this across the far SE where surface dew points are a little higher, but this still could occur farther NW as well.

Significant changes are on the way by the end of the week, with very good model agreement that a flat upper ridge over the southern US will start to amplify by the weekend and become anchored from the Gulf coast to off the SE coast. Surface high pressure parked offshore will allow southerly flow to prevail, leading to above normal temperatures returning by the weekend, with highs in the upper 80s and nearing 90F possible. Current ensemble guidance shows a high probability for highs into the 90s Sun-Tue (especially Mon- Tue) for much of the area, and the antecedent drought conditions should make this rather easy to occur.

AVIATION /00Z THURSDAY THROUGH MONDAY/
As of 755 PM EDT Wednesday...

A cold front is located just W of the area this evening, and will push through the terminals between 03z and 09z tonight.
Ahead of the front, light rain is possible at RIC over the next few hours. Otherwise, cloud cover will thicken and lower as the front approaches, with CIGs potentially becoming MVFR for a period tonight. A line of more organized shower activity will push through between 03 and 10z and an isolated rumble or two of thunder is also possible. While prevailing VFR VSBY is expected, there is a low chance (20-30%) of brief VSBY reductions if a heavier shower moves through a terminal. Have therefore introduced some PROB30 groups in the TAFs. Some model guidance also depicts a brief (potential) period of IFR CIGs at ECG from 08-10z, but confidence in this is not particularly high. Showers should gradually end from W to E around sunrise Thursday, with an isolated shower or two potentially lingering into Thursday afternoon in NE NC. S-SSE winds this evening/early tonight shift to the N-NW behind the front late tonight, and remain out of the N and increase to 10-15 kt with gusts to 20 kt during the day Thursday.

Outlook: VFR conditions are expected later Thursday. Dry and VFR conditions continue Fri-Mon.

MARINE
As of 225 PM EDT Wednesday...

Key Messages:

- Small Craft Advisories remain in effect into this evening for the Chesapeake Bay and tidal rivers due to strong southerly winds ahead of a cold front.

- Additional SCAs are likely Thursday into Thursday night with N-NW surges behind the cold front.

- Generally benign conditions return Friday AM through much of the weekend into early next week with winds generally out of the S to SW.

This afternoon, ~1024 mb high pressure is located well off the Mid Atlantic coast. Meanwhile, ~1002 mb low pressure is located over the northern Great Lakes with a cold front extending south into the Ohio Valley. This front will approach the waters later this afternoon into this evening before crossing the waters tonight. Ahead of the front, gusty S to SSE winds continue, especially over the Chesapeake Bay, with gusts of 20-25 knots. Winds will continue to increase as we head through this afternoon with occasional gusts to ~30 knots possible, especially over the Chesapeake Bay and tidal rivers. Small Craft Advisories remain in effect for all of the aforementioned locations into tonight.

Winds quickly diminish and become W-NW after 10 PM tonight as the cold front crosses the waters. In the wake of the front, there will be a brief lull in the wind before a N-NW wind surge kicks in later Thursday morning. Another round of SCAs will be needed for the Chesapeake Bay tomorrow morning with gusts of 20-25 knots possible.
Another surge of N-NW winds is expected Thursday night into early Friday as drier air filters over the waters. SCAs will likely be needed for a majority of the waters due to the combination of 25+ knot wind gusts and seas building to 5 feet. After Friday AM, mainly benign marine conditions are forecast through a majority of the weekend and into early next week, with winds primarily out of the S to SW. There may be brief periods of southerly surges approaching SCA levels, with the best potential Saturday night into Sunday morning over the coastal waters.

AKQ WATCHES/WARNINGS/ADVISORIES
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 1 AM EDT Thursday for ANZ630>632- 634.
Small Craft Advisory until 10 PM EDT this evening for ANZ635>637-639.