textproduct: Wakefield

WHAT HAS CHANGED

- Increased high temperatures a degree or two for tomorrow (Wednesday)

- Lowered high temperatures for Thursday

- Winds have trended higher behind the strong cold front passage later Friday into Saturday. Confidence in Gale conditions also continues to increase.

KEY MESSAGES

1) Well above normal temperatures with mostly dry conditions are expected through Friday. Record breaking highs are possible Wednesday.

2) A strong cold front crosses the area Friday evening, with gusty winds expected ahead of and behind the front. A few showers and storms are also possible in the afternoon and evening hours of Friday.

3) Much cooler temperatures arrive this weekend. Frost is possible across portions of the area.

DISCUSSION

As of 315 PM EDT Tuesday...

KEY MESSAGE 1...Well above normal temperatures with mostly dry conditions are expected through Friday. Record breaking highs are possible Wednesday.

Sunny skies and warm (for mid-October) temperatures are ongoing across our forecast area this afternoon. Rising heights are noted in the mid and upper levels, with high pressure centered south of the area at the surface. A weak shortwave slides through overnight, but this feature will not have any noticeable impact on the local weather. Overnight lows continue the mild trend...generally in the lower to mid 60s.

The peak in the heat is still expected on Wednesday, with high confidence in record-breaking temperatures for most of the area. This will occur as the ridge axis aloft shifts eastward from the TN/OH Valleys. Highs at least in the upper 80s are almost a given, and a blend of the various hi-res and statistical guidance yields highs of 90-92 F for most areas W of the Chesapeake Bay. As noted by the previous shift, the statistical guidance remains a few degrees higher than the NBM, so there certainly is some room for temps to overperform some. Regardless, highs should be well into record territory with daily records only in the mid to upper 80s. See climate section below for site-specific data. While these temperatures resemble mid-summmer values, dew points in the lower to mid 60s should suppress the "mugginess" factor.

A cold front will approach the region from the N Wednesday night and is forecast to drop through the local area Thursday morning. Transient high pressure will also set up over interior New England, so a brief wedge-like pattern is possible during most of the day with onshore flow and cool/cloudy skies. With increasing confidence in the frontal passage occuring before peak heating, have lowered highs ~2-4 degrees compared to the previous forecast and the NBM. This is more in line with most of the traditional model guidance and ultimately would not be surprised if temps trend even cooler. Exact timing of temps remains a challenge due the the frontal passage, but daytime highs are likely to be achieved on the earlier side and range from the 70s/lower 80s S to 60s across the northern tier. Clouds will also thicken from N to S Thursday as the front drops south. In addition, some weak isentropic lift/overrunning north of the front could result in generally light rain across the northern third of the area Thursday. QPF is on the order of a few hundredths of an inch.

KEY MESSAGE 2...A strong cold front crosses the area Friday evening, with gusty winds expected ahead of and behind the front. A few showers and storms are also possible in the afternoon and evening hours of Friday.

A deep upper trough is forecast to dig across the Great Lakes Thursday night into Friday with a strengthening surface low over the Ohio Valley. This will quickly erode any wedge-like airmass and allow a quick transition back to deep-layer S/SW flow as the front lifts back N as a warm front. High temps rebound into the upper 70s to low 80s N with mid and upper 80s S. It will become breezy out of the SW by Friday afternoon, with gusts to 30-35 mph possible. Scattered showers are also probable ahead of an associated strong cold front, particularly across N and NE portions of the local area. An embedded storm or two is also possible but this is dependent on the degree of available instability. Any shower/storm could mix down locally higher wind gusts and a Marginal (level 1/5) severe risk may eventually be needed, per SPC.

Rapidly deepening low pressure will translate from the Great Lakes into the New England region by Friday night, with the aforementioned sharp/strong cold front extending southwestward. This front will cross the local area Friday evening into early Saturday with significant cold advection moving into the region. Some additional precip is possible along and ahead of the frontal passage through midnight, mainly over the eastern half of the area. QPF does not look nearly as impressive as a front of this strength would suggest, mainly due to the unfavorable trough orientation and disconnect from any appreciable moisture sources. However, gusty winds are likely to continue into the Friday overnight period and could reach 35-40 mph immediately along and behind the front.

KEY MESSAGE 3...Much cooler temperatures arrive this weekend. Frost is possible across inland portions of the area.

Strong (1035mb+) high pressure builds into the region behind the front with upper troughing remaining over the eastern CONUS, resulting in well below normal temperatures this weekend. Afternoon highs on Saturday likely struggle to get out of the 50s across the northern half of the CWA despite mostly sunny skies. Low 60s are forecast for the southern half of the area. Breezy conditions continue into the daytime hours of Saturday with gusts of 25-30mph, and especially near the coast where winds could gust 30-35mph. Overnight low temps tumble into the mid to upper 30s in the Piedmont with low to mid 40s for the remainder of the area Saturday night. Upper 30s and low 40s are forecast Sunday night into Monday. Some frost is possible in the Piedmont with this airmass, particularly if the lower temperatures (in the 32-35 F range) depicted by the MOS guidance is realized.

A gradual warming trend is possible by early next week and the latest CPC medium range outlook favors above-normal temperatures through the end of the month.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

As of 110 AM EDT Wednesday...

VFR will prevail through the 06z TAF period. Some mid level stratus and even a few light showers are noted across the Northern Neck and MD Eastern Shore. This activity should move offshore over the next hour or two. SW winds ~5 kt early this morning will become SW 5-10 kt through the afternoon. A cold front will drop southward into the area very late in the period with winds becoming N behind the boundary.

Outlook: A cold front drops south later tonight into Thursday, bringing increased cloud cover and low-end rain chances to portions of the area. Sub-VFR CIGs are possible Thursday into Friday morning as a wedge pattern develops over the area. Another cold front crosses the area Friday into Saturday, bringing additional rain chances and gusty NW winds.

MARINE

As of 240 PM EDT Tuesday...

Key Messages:

- Benign marine conditions prevail through Thursday night.

- A strong cold front crosses the waters late Friday into this weekend. Strong SCA to Gale conditions are likely Friday night through early Sunday.

Latest analysis reveals W-SW winds ~10 kt across the region this afternoon, as high pressure builds along the southeast coast. Waves 1 ft or less on the rivers, Sound, and Bay. Seas averaged 2-3 ft.

High pressure builds just offshore of the coastal Carolinas through midweek, with mainly pleasant/benign boating conditions expected through Wed night. S-SW winds persist tonight and tomorrow 5-10 kt, turning S-SE nearshore with the afternoon sea breeze. A backdoor front still looks to drop across the waters late tomorrow night into Thursday, with winds veering to the NNE post-frontal. Winds look to remain mainly sub-SCA (~15 kt Rivers/Bay/Sound, ~20 kt over the coastal waters) through this period. However, internal wind probability guidance continues to key-in on a short period of low-end SCA-level winds in the lower Bay Thursday morning. Guidance shows a 50-70% probability of winds ~20 kt in this area between 8 am and around noon on Thursday, before winds diminish and veer to the S-SE Thu afternoon and evening. Wind waves from the onshore flow should also increase seas to 3-4 ft during this period, with waves 2-3 ft, highest at the mouth of the Bay.

A quickly deepening surface low over the eastern Great Lakes Friday and Friday night still looks to push a second, much stronger cold front toward the local waters late Friday into the weekend. The compressing gradient ahead of that front will likely result in increasingly gusty S-SW winds late Friday morning and especially Friday afternoon, and a short period of SCA-level winds are possible. That front crosses the waters Friday night into Saturday morning, with strong SCA-level winds forecast for all waters. Local wind probs are also showing that Gale Force gusts are looking increasingly likely, with probabilities trending up to 30-70+% in the bay and 80-90% over the coastal waters, peaking also in the same late Friday night to midday Saturday time frame.

Transient high pressure is quick to slide in behind the front Saturday afternoon into Sunday, allowing winds to veer to the NNE and gradually diminish Saturday night into Sunday morning. Waves/seas peak Saturday afternoon and evening, ranging from 3-6 ft over the Bay and 5-8 ft over the coastal waters.

CLIMATE

Record High Temperatures:

10/13 10/14 RIC 90/1954 87/1975 ORF 89/1954 86/1975 SBY 86/1954 86/1975 ECG 87/1990 86/1975

AKQ WATCHES/WARNINGS/ADVISORIES

MD...None. NC...None. VA...None. MARINE...None.