textproduct: Columbia

WHAT HAS CHANGED

Not much change in the overall forecast. Aviation discussion updated for 12z TAFs.

KEY MESSAGES

- 1. Dry, warm weather favored through the week.

- 2. A strong cold front is forecast to push through the region Friday night, ushering nice Autumnal weather.

DISCUSSION

Key Message 1: Dry, warm weather favored through the week.

Confidence remains high in above normal temperatures remaining in place through Friday afternoon. Strong, anomalous ridging is forecast to overspread the area over the next several days. NAEFS 500 hPa heights are expected to be near the model climate's max for this time of year. With a relatively dry (PWs ~1") in place & sunny skies, we are looking at near record highs across the area Wed-Fri. Highs of 86F-90F look likely in this period, with lows likely rebounding a bit into the low 60s given relatively low dewpoints for such a warm airmass. The EFI values are sitting around 0.75-0.85 each day, confidence is high that anomalous temps will continue. Still think that Thur/Fri have the best chances for temps bumping up above 90 despite the NBM slightly cooling temps for Friday especially. The combination of strong southwesterly flow and compressional heating ahead of a cold front should yield ideal conditions for a record to break.

Key Message 2: A strong cold front is forecast to push through the region Friday night, ushering nice Autumnal weather.

Guidance is in good agreement on the overall pattern heading into this weekend. A deep trough is forecast to develop over the central US over the next couple of days and begin marching eastward, pushing a strong cold front along with it. This will occur in conjunction with a strong, anomalous surface high pressure pushing out of the upper Midwest and into the Mid- Atlantic by this weekend. There is some minor spread in the timing of the front but in general it is forecast to push through the area easily on Friday night, with a much welcomed cool down following in its wake. This is driven by a surface high that is expected to be on the order of 1040 mb, which is near the 99th percentile for strength this time of year. Guidance is tightly clustered for highs and lows this weekend into early next week as a result, with well-below normal temps in the 60s on Saturday and Sunday, bumping back up into the low 70s by early next week. Overnight lows look chilly, with 40s likely across most of the area. Our cooler spots may flirt with the 30s given the low dewpoint airmass! Additionally, expect it to be breezy on Friday night and Saturday. The EFI wind gust signal is pretty good (~0.7-0.75) for Saturday, with gusts of 30+ mph expected behind such a strong front.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

VFR outside of potential early morning patchy fog.

Clear skies and light winds through the day with high pressure over the region. Calm winds overnight and clear skies will allow for excellent radiational cooling conditions and for another round of brief, early morning fog at our fog-prone sites. Although fog may form at AGS and OGB, we have kept the TAFs VFR due to low confidence in the exact timeframe of the brief potential fog. Light winds continue Wednesday with winds generally out of the SW but could be variable much of the day.

EXTENDED AVIATION OUTLOOK...A front will move across the area late this week and early weekend. Although precipitation is unlikely, breezy W/SW winds are expected Friday shifting to northerlies Saturday.

CAE WATCHES/WARNINGS/ADVISORIES

SC...None. GA...None.