textproduct: Raleigh

WHAT HAS CHANGED

* No significant changes from previous forecast thinking

KEY MESSAGES

As of 148 AM Tuesday...

1) Dry today, cool tonight.

2) A dry week mid to late week is expected. Temperatures will warm to above normal from Wednesday through Saturday. The next chance of rain returns this weekend, but most of it may hold off until Sunday.

DISCUSSION

As of 148 AM Tuesday...

KEY MESSAGE 1... Dry today, cool tonight.

A dry cold front was located over southern VA this morning, identified not only by a southward progressing pre-frontal stratocu deck, but also by decreased dewpoints in the 40s. Ahead of the front across central NC, lingering mid/upper 50s dewpoints and light/calm winds have supported some patchy fog since late Monday evening. Between the southward progressing stratocu deck, increased mixing, and the subsequent arrival of lower dewpoints, it's expected that fog should gradually dissipate as the morning goes on. I'll keep a mention of patchy fog in the forecast through daybreak but conditions should gradually improve.

All in all, it should be a quiet weather day once the front moves through. Winds may briefly gust this morning as the BL deepens and taps into the 25-30kt 925mb winds, but this should rapidly diminish through the day. It'll be cooler today with temps generally in the upper 60s (north) to mid 70s (south). The more noticeable cooldown will come tonight. Between clear skies and light/calm winds, look for lows to easily bottom out in the low to mid 40s, if not upper 30s in the normally cooler/protected areas.

KEY MESSAGE 2... A dry week mid to late week is expected. Temperatures will warm to above normal from Wednesday through Saturday. The next chance of rain returns this weekend, but most of it may hold off until Sunday.

The dry and cool surface high pressure will move off the Mid- Atlantic coast Wednesday and Wednesday night. A dry reinforcing cold front will slip through NC late Thursday and Thursday night. Therefore, sunny and dry conditions are expected Wednesday with highs in the upper 70s to lower 80s. As the winds become SW at 10-15 mph ahead of the front Thursday, there will be little moisture to work with. Expect mainly sunny skies and warming temperatures into the mid 80s. Record daily highs are in the lower to mid 90s, so they are not in play. It will be slightly cooler behind the front Friday with highs around 80. Lows will be mostly in the lower to mid 50s this week, warmest Friday morning (near 60 in some locations).

The next chance of showers appears to be over the weekend. There continues to be quite a bit of model spread with the potential Gulf to SE United States system, with the EC ensemble continued to be preferred, which may obviously change with time. As of right now, the EC depicts higher rain chances have moved 6-12 hours later than previously forecast. The period between Saturday night through Monday morning appear to be when the most significant rain will fall.

AVIATION /06Z TUESDAY THROUGH SATURDAY/

As of 148 AM Tuesday...

Patchy fog has developed across central NC ahead of the approaching cold front, which is still positioned over VA as of 05Z. RWI has been the only TAF site directly affected but a number of other sites have reported vsbys of 1SM or lower. Meanwhile, a VFR stratocu deck around 3500ft has formed immediately ahead of the front and is migrating southward. Between the stratocu and some increased mixing just off the surface with the southward progressing 925mb front, vsbys are rapidly improving. I'll leave an hour or two of IFR/LIFR vsbys in the RWI TAF, otherwise VFR weather should prevail at RWI and elsewhere for the morning hours. The stratocu deck will eventually move through NC, reaching all sites between 06Z-12Z, but this will quickly mix out and dissipate by late morning. Clear/mostly clear skies to follow this evening into Wednesday morning. With substantially lower dewpoints forecast from this morning onward, the threat of fog should be nil early Wednesday morning.

As for winds, all sites should see borderline LLWS conditions through daybreak as the 925mb front slides through the area. Between surface winds around 5-8kts and 925mb winds around 30kts, LLWS should be marginal and I'll keep it out of the TAFs unless surface winds remain calm.

Outlook: VFR weather expected through the first part of the weekend. Increased moisture arriving this weekend could result in periods of non-VFR weather late Saturday into early next week although timing/confidence in the specifics is low at this point. Rain chances appear to be highest on Sunday.

RAH WATCHES/WARNINGS/ADVISORIES

None.