textproduct: Wilmington

WHAT HAS CHANGED

Light snow probability decreased and shifted a bit further south on Tuesday/night. This resulted in expected accumulations less than an inch.

KEY MESSAGES

1) Frigid temperatures will continue through this weekend.

2) Periods of light snow possible throughout the week, with best chance of light accumulations Thursday night into Friday.

DISCUSSION

KEY MESSAGE 1) An arctic air mass will linger across the middle Ohio Valley through this weekend. The center of anomalously cold surface high pressure will slowly shift east from the southern Plains this afternoon into the lower Mississippi Valley Sunday, then to the central and southern Appalachians Monday. High temperatures will slowly rise into the 20s to low 30s Monday and Tuesday on the back side of the high before dropping back into the teens Wednesday and Thursday. At this time, ensemble guidance does not produce a high- confidence thaw through the period.

KEY MESSAGE 2) A very weak disturbance will slide through the Great Lakes Monday as the surface high shifts to our east. Latest guidance remains rather dry. However, have continued to add a slight chance of snow across our northern counties since it won't take much moisture and lift in this very cold air mass.

Another weak system will move from the lower Mississippi Valley to the southeastern United States Tuesday and Tuesday night. This system has trended further south on our latest model runs, so coverage of precipitation as well as potential accumulations have been reduced... now with less than an inch across our southern zones.

A more significant mid-level shortwave drops southeast into the lower Lakes Thursday night and Friday. Isentropic lift ahead of the wave will bring snow chances back across our area, with a focus over our northern counties. Will need to continue to monitor this system as far as potential light snow accumulations and also wind and reinforced arctic air behind it heading into next weekend.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

Pesky stratocumulus clouds will continue to bring periods of MVFR ceilings early in the TAF period due to northerly flow over the Great Lakes. Can't rule out a few flurries, but generally expecting dry conditions and VFR visibilities. Clouds coverage will decrease late tonight into Sunday as winds become more westerly and southwesterly.

OUTLOOK...MVFR CIGs and VSBYs are possible on Monday and then again Tuesday into Tuesday night.

ILN WATCHES/WARNINGS/ADVISORIES

OH...Cold Weather Advisory from 10 PM this evening to 10 AM EST Sunday for OHZ026-034-035-042>046-051>056-060>065-070>074-077>082-088. KY...Cold Weather Advisory from 10 PM this evening to 10 AM EST Sunday for KYZ089>100. IN...Cold Weather Advisory from 10 PM this evening to 10 AM EST Sunday for INZ050-058-059-066-073>075-080.