textproduct: Columbia

WHAT HAS CHANGED

Aviation discussion updated for 12z update.

KEY MESSAGES

- 1. The stretch of dangerous heat continues.

- 2. Storm coverage will be limited again today, with increasing potential late week into the weekend.

DISCUSSION

KEY MESSAGE 1: The stretch of dangerous heat continues.

A weak front will move into the area today ushering in slightly drier low-level air, especially north and west of I-20. Having said that, forecast highs will be in the mid-90s to around 100 degrees today so appropriate heat precautions need to be made during peak heating hours, even for the counties not included in today's Heat Advisory. Locations along and east of the I-95 corridor as expected to see the highest Heat Index values today, which could approach 110 degrees. The dangerous summer heat and humidity continues through Friday with max heat indices around 105 degrees each day so which our advisory criteria may not be met, significant relief from the heat remains unlikely until the weekend when the ridge finally breaks down and there will be increased chances for precipitation.

KEY MESSAGE 2: Storm coverage will be limited again today, with increasing potential late week into the weekend.

A capping inversion similar to yesterday is expected again today across the FA, which should limit any convection despite weak convergence along a surface front. However, given the heat and humidity in place an isolated shower or thunderstorm cannot be completely ruled out, especially closer to the Coastal Plain. Scattered afternoon thunderstorms will be possible each afternoon Wednesday and Thursday as moisture begins to increase, with widespread convection Friday through the weekend with a robust mid-level trough moving into the eastern CONUS and deep layer southwest flow leading to increased moisture.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

VFR conditions expected through the TAF period. An isolated storm is possible but impacts to the terminals are unlikely.

Winds will remain light and variable then pick up around midday out of the west-northwest from 5 to 10 kts. A few cumulus are expected to develop into the afternoon hours. An isolated shower or thunderstorm cannot be completely ruled out in the afternoon or evening but coverage will be so low that convection was not mentioned in the TAFs. Winds will go light or calm again around 00Z. Patchy fog is possible early Wednesday morning at AGS but high and mid clouds overnight should suppress widespread fog concerns.

EXTENDED AVIATION OUTLOOK...Diurnal chances for thunderstorms increase each day through the end of the week.

CAE WATCHES/WARNINGS/ADVISORIES

SC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening for SCZ016-022-027>031-035-037-038-041-135>137. GA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening for GAZ064-065-077.