Excessive Heat in Florida, August 6 to 9, 2023

Area Forecast Discussion
National Weather Service Tallahassee FL
924 AM EDT Sun Aug 6 2023

...New UPDATE...

.UPDATE...
Issued at 924 AM EDT Sun Aug 6 2023

Previous forecast appears to be on track. No major updates were
needed.

&&

.NEAR TERM...
(Today and tonight)
Issued at 306 AM EDT Sun Aug 6 2023

Some patchy fog to the start of what will be a dangerously hot day
with the potential for isolated severe thunderstorms this afternoon
and evening. The main forcing mechanism for convection today will
be a mid-level shortwave, with additional contributions from the
seabreeze circulation. PoPs are highest northwest of I-10 and the
Flint River, ranging from 50-70 pct, and 30-50 pct southeastward,
as northwest 850 hPa flow tends to supress the seabreeze. Model
soundings indicate high instability, with SB CAPE up to 5k J/kg,
and DCAPE in excess of 1k J/Kg. The main concern will be pulse-
type thunderstorms, with isolated damaging wind gusts and small
hail. The greatest potential will be in the Western FL Panhandle,
Southeast AL, and Southwest GA. The deep layer flow is weaker
compared to yesterday, only around 10 knots. This combined with
PWATS in excess 2.0" may lead to isolated flash flooding due
to slow moving/training storms producing high rainfall rates.
Convection is expected to hold off long enough for higher heat
indices/apparent temperatures across the entire region compared
to yesterday. The Heat Advisory has been expanded to include all
of the Southwest GA Counties, and continues in Southeast AL and
FL Big Bend Counties. The Heat Advisory in the FL Panhandle and
portions of Southeast AL has been replaced with an Excessive
Heat Warning. Thus, dangerous heat is expected across the entire
region today, with heat index values ranging from 107-115 deg.

&&

.SHORT TERM...
(Monday through Tuesday night)
Issued at 306 AM EDT Sun Aug 6 2023

East-west oriented subtropical ridge will remain parked south of
the region through much of the upcoming week, keeping the forecast
area on the southern edge of the mid-latitude westerlies. West-
southwest flow in the lowest levels will keep the boundary layer
very moist through Tuesday, with dewpoints staying in the mid to
upper 70s. The west-northwest mid-level flow will support keep
temperatures above normal, with highs reaching the mid to upper
90s each afternoon. The combinations will push apparent
temperatures well above 100 degrees, and above 110 degrees in some
areas. Most of the area will likely need another Heat Advisory for
Monday, with and Excessive Heat Warning possible for southern
portions. Have gone ahead with and Excessive Heat Watch for this
southern area. Not a whole lot of change is expected for Tuesday.

Scattered showers and thunderstorms will be possible each day,
with potentially better chances on Tuesday as a slightly stronger
shortwave moves through in the zonal flow aloft. Isolated severe
storms will be possible each day, with damaging winds being the
primary threat.

&&

.LONG TERM...
(Wednesday through Saturday)
Issued at 306 AM EDT Sun Aug 6 2023

The overall pattern stays the same through most of the week, with
hot and humid conditions continuing. Some slightly drier air may
advect in by late Wednesday or Thursday, possibly lowering PoPs
for or a day or so. Otherwise, the above normal temperatures are
expected to continue into next weekend.

&&

.AVIATION...
(12Z TAFS)
Issued at 628 AM EDT Sun Aug 6 2023

Brief restrictions to MVFR in fog this morning at VLD. Also,
cannot rule out brief fog at the other terminals, but the
probability is low, so VFR should prevail. For today, highest
confidence in TSRA is at ABY, DHN, and TLH, where TEMP groups were
used to convey brief restrictions to MVFR. At ECP and VLD, VCTS
should do it for now. Confidence in timing is medium, but overall
later than y'day. For tonight, some MVFR restrictions possible
late at ABY and DHN, but low confidence attm.

&&

.MARINE...
Issued at 306 AM EDT Sun Aug 6 2023

Generally light west to southwest flow is expected to prevail
across the coastal waters through the weekend into early next
week, keeping seas generally two feet or less. Scattered
thunderstorms may lead to locally higher winds and seas.

&&

.FIRE WEATHER...
Issued at 306 AM EDT Sun Aug 6 2023

Transport winds have come down slightly today so dispersions
across Southeast Alabama are expected to remain in the 40s
and 50s. Stronger transport winds on Monday are expected to
lead to high dispersions across portions of Southeast AL
and Southwest GA. A prolonged period of dangerous heat is
on tap beginning today and continuing into early next week
with heat index/apparent temperatures ranging from 107 to
around 115 degrees each day.

&&

.HYDROLOGY...
Issued at 306 AM EDT Sun Aug 6 2023

Daily diurnal convection through the next several days will lead
to widespread rainfall amounts generally less than two inches.
However, with plenty of deep moisture in place, locally heavier
amounts could lead to some localized flooding.

&&

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   96  76  98  77 /  40  20  40   0
Panama City   93  80  93  82 /  30  20  20  10
Dothan        96  75  97  77 /  60  30  20  10
Albany        97  75  97  77 /  50  50  20  10
Valdosta      96  74  98  76 /  40  30  30  10
Cross City    94  77  94  78 /  40  20  40  10
Apalachicola  92  80  92  82 /  40  20  30  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Excessive Heat Warning until 8 PM EDT /7 PM CDT/ this evening
     for FLZ007>010-012>014-108-112-114.

     Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for FLZ011-
     015>019-026>029-034-115-118-127-128-134.

     Excessive Heat Watch from Monday morning through Monday evening
     for FLZ007>019-026>029-034-108-112-114-115-118-127-128-134.

GA...Heat Advisory until 8 PM EDT this evening for GAZ120>131-142>148-
     155>161.

     Excessive Heat Watch from Monday morning through Monday evening
     for GAZ155>161.

AL...Excessive Heat Warning until 7 PM CDT this evening for ALZ065-
     068.

     Heat Advisory until 7 PM CDT this evening for ALZ066-067-069.

     Excessive Heat Watch from Monday morning through Monday evening
     for ALZ068-069.

GM...None.
&&

NEAR TERM...LF
SHORT TERM...Camp
LONG TERM....Camp
AVIATION...LF
MARINE...Camp
FIRE WEATHER...LF
HYDROLOGY...Camp