textproduct: Wilmington

WHAT HAS CHANGED

Made some tweaks to pops and snow amounts across our south for late tonight/Thursday morning.

KEY MESSAGES

1) Chances for light snow tonight

2) Potential weather system for early next week.

DISCUSSION

KEY MESSAGE 1)

A mid level short wave will track east across the Ohio Valley late tonight into Thursday morning. For this being less than 24 hours out, there still remains an unusual amount of uncertainty with the models with this system in terms of timing, placement and strength. There does at least seem to be some consensus in the best chance of any pcpn to be across our southern areas so have trended pops in that direction. However, the exact track and strength of this system will also help determine ptype and any snow amounts.

Based on model blends, it looks like pcpn would be mainly snow along and north of the Ohio River and more of a snow or rain/snow mix to the south. A couple of the hi-res models and the latest GFS are still showing some localized amounts of 1-2 inches somewhere across our south and this is backed up by the GFS ensemble mean which continues to show a mean of around 1 inch across parts of our south. Meanwhile, the NAM, and a couple other hi-res models have little if any snow or are mostly dry. This all makes for a low confidence forecast -- but given some of the "higher end" potential and the fact that this will be moving in toward the morning rush, am hesitant to go as low as what is indicated by the NBM. Will therefore nudge pops and QPF up somewhat (closer to what is suggested by the ECMWF, which has trended to around a half inch or so of snow across parts of our south). Will also add some conditional wording to the HWO for the potential of some light snow during the morning rush across the south.

KEY MESSAGE 2)

In quasi-zonal flow, mid level energy will move out of the Rockies over the weekend and toward the east coast through early next week. Guidance continues to suggest the potential for a surface wave to develop across the Tennessee/Ohio Valley regions Sunday into Monday. Still a lot of time for models to further resolve this but as of now, there looks to be a potential for accumulating snow Sunday into Monday, with the best chance for this across our northern areas.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

A weak upper level disturbance will move through the Ohio Valley later tonight into Thursday morning. This will lead to a developing chance for snow through the predawn hours and then continue into mid morning Thursday. The best chance for this appears to be at the southern TAF sites where some MVFR to locally IFR conditions will be possible in the 09Z-13Z time frame. Conditions will improve through late morning with VFR conditions returning toward the end of the TAF period.

OUTLOOK...MVFR to IFR conditions possible Sunday into Monday.

ILN WATCHES/WARNINGS/ADVISORIES

OH...None. KY...None. IN...None.