textproduct: Columbia

WHAT HAS CHANGED

Key messages and aviation discussion updated for 18z TAF.

KEY MESSAGES

- 1) A warming trend this week will lead to well above normal temperatures, especially Wednesday through Friday.

- 2) Rain chances look to increase again late this week and especially this weekend.

DISCUSSION

KEY MESSAGE #1: A warming trend this week will lead to well above normal temperatures, especially Wednesday through Friday.

Temps will steadily warm, pushing record highs for the latter half of the week. Broad ridging and offshore Bermuda high pressure will drive consistent southwest flow in the region and drive 500mb heights and 850mb temps above the 95th percentile in the NAEFS; EC EFI lines up well not surprisingly, with a typical high EFI but relatively low SoT. In terms of sensible weather this will yield temps into the mid-upper 70's for mid- week and then pushing 80F by the end of the week.

KEY MESSAGE #2: Rain chances look to increase again late this week and especially this weekend.

Eventually the persistent southwesterly flow into the region will drive PWAT's back above average by late week and into the weekend. Questions continue on exactly how quickly the deep Pacific troughs will eject eastward, which will determine when sufficient forcing for any appreciable rain will reach our area. Within the GEFS and ECE, timing is uncertain, but eventually this trough will bring some elevated rain chances. Because of the timing uncertainty, the NBM is effectively smoothing out PoP's from Friday through Monday, so in actuality rain will not occur everyday, rather in a shorter window.

AVIATION /18Z MONDAY THROUGH SATURDAY/

Early morning fog possible at AGS and OGB, otherwise VFR.

Winds will diminish through the remainder of the day as surface high pressure builds over the region. NE winds around 5 to 10 kts expected through 00Z before light and variable or calm winds develop. Light winds overnight and lingering low level moisture is favorable for patchy fog at our most fog prone sites, AGS and OGB. A few high clouds may build into the region overnight and limit confidence in widespread fog. HRRR does show some patchy fog but mainly restricted to north and west of the TAF sites. The most likely timing for fog at AGS/OGB would be between 06Z and 12Z. Light southerly winds pick up Tuesday morning with weaker gusts than seen the previous morning.

EXTENDED AVIATION OUTLOOK...Moisture increases through the week leading to increasing chances of morning fog/stratus. The next chance of rain will be Thursday.

CAE WATCHES/WARNINGS/ADVISORIES

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