Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
467
FXUS62 KTAE 220817
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
417 AM EDT Fri Aug 22 2014

.Near Term [Through Today]...
As it was on Thursday, the dreaded (and possibly deadly) combination
of Heat and Humidity will be the primary story for today (and
beyond) once again. In fact, with high temperatures expected to rise
to between 100 and 103 inland and 95 to 98 near the coast, Heat
Indices are expected to peak out between 113 and 115 degrees across
much of the FL Panhandle as well as Leon and Wakulla counties in the
FL Big Bend this afternoon due to Sfc dewpoints holding in the mid
to upper 70s while the temps keep rising. This dangerous combination
of Heat and Humidity will result in the issuance of an Excessive
Heat Warning today for these areas. Further to the north and east,
temperatures will still be just as hot, but dewpoints are expected
to mix out a little bit more, falling into the lower 70s around
the time of the highest temperatures. This will still result in
maximum Heat Indices between 108 and 112 degrees which will still be
extremely uncomfortable and dangerous for any outdoor activities. As
for rain chances, with light offshore flow at the sea breeze layer
(1000-700 mb) and slightly drier air building in at mid-levels,
reduced PoPs slightly from the previous package, going with
generally 20% across N FL, using a blend of Sea Breeze Climo with
mid-level theta-E, the previous official fcst, and Gridded MOS for
this aftn.

.Short Term [Tonight Through Sunday]...
High pressure will remain in place across the Mid South and
continue the heat wave into Saturday across our region. There is
some split between the guidance whether the ridge axis will shift
far enough west on Saturday to allow for better than isolated
coverage of showers and storms. The GFS/Euro suggest limited storm
coverage and a hot afternoon. Some differences also exist with
whether we`ll mix out in the afternoon and get dewpoints in the
upper 60s. There were some mid 60s dewpoints around the region on
Thursday, but model soundings by Saturday afternoon show limited
potential to mix drier air to the surface, so feel dewpoints are
likely to stay in the 70s on Saturday. Heat advisory conditions
are a certainty with the potential for excessive heat warning
criteria across the Florida Big Bend.

By Sunday, model guidance agrees that the ridge axis will shift
further westward and amplify between two troughs. With a trough
digging down the eastern seaboard, our region will be in a favored
location for late day MCS activity. Because it will probably be
late afternoon before storms get going, temperatures will still
warm into the upper 90s to near 100, and create another day of
heat advisory conditions with heat indicies in the 106 to 110
degree range.

.Long Term [Sunday Night Through Friday]...
Northwesterly low-layer flow will veer to a more easterly
direction increasing boundary layer moisture, while deep layer
ridging persists. This increase in moisture will result in near
normal PoPs to start the period. By early next week there is
consensus that a front will slip into the region from the
northeast returning us to a drier than normal pattern to finish
the week. Temperature will remain closer to seasonal normals for
the entire extended range.

&&

.Aviation...
[Through 12Z Saturday] VFR conditions are expected to prevail
through the period, and the only changes made from the previous
package to add brief periods of MVFR level Vis at ECP and ABY,
which received around 0.5" and 0.25" inches of rain respectively
earlier in the day on Thursday. Otherwise, expect very hot and
humid conditions to dominate the terminals today. Cannot rule out
an isolated tstm at the southern terminals, but believe chances
are too low to mention at this time.

&&

.Marine...
Generally light winds and low seas will continue through the
weekend. Winds and seas will be on the increase on Monday as the
gradient tightens between an area of high pressure across the Mid
Atlantic States and a tropical system moving east of the Bahamas.
Cautionary conditions are possible by Tuesday.

&&

.Fire Weather...
With plenty of heat and high humidity, no Red Flag conditions are
expected anytime in the near future.

&&

.Hydrology...
Very little rainfall is expected over the next few days and river
levels will remain well below action stage. In fact, the
Apalachicola River is forecast to remain in low flow levels into
next week.

&&

.Preliminary Point Temps/PoPs...

Tallahassee  102  75 100  77  99 /  20  10  20  20  40
Panama City   96  80  96  81  96 /  20  10  20  10  20
Dothan       101  76 101  76 100 /  10  10  10  10  40
Albany       102  76 101  76  99 /  10  10  10  10  50
Valdosta     103  75 102  75  98 /  10  10  20  20  50
Cross City    99  76  98  77  96 /  20  10  20  20  40
Apalachicola  95  80  94  81  94 /  20  10  20  10  20

&&

.TAE Watches/Warnings/Advisories...

FL...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for Coastal Dixie-Coastal Jefferson-Coastal Taylor-Inland
     Dixie-Inland Jefferson-Inland Taylor-Lafayette-Madison.

     Heat Advisory from 11 AM EDT /10 AM CDT/ to 8 PM EDT /7 PM CDT/
     Saturday for Calhoun-Central Walton-Coastal Bay-Coastal
     Dixie-Coastal Franklin-Coastal Gulf-Coastal Jefferson-
     Coastal Taylor-Coastal Wakulla-Gadsden-Holmes-Inland Bay-
     Inland Dixie-Inland Franklin-Inland Gulf-Inland Jefferson-
     Inland Taylor-Inland Wakulla-Inland Walton-Jackson-
     Lafayette-Leon-Liberty-Madison-South Walton-Washington.

     Excessive Heat Warning from 11 AM EDT /10 AM CDT/ this morning
     to 8 PM EDT /7 PM CDT/ this evening for Calhoun-Central
     Walton-Coastal Bay-Coastal Franklin-Coastal Gulf-Coastal
     Wakulla-Gadsden-Holmes-Inland Bay-Inland Franklin-Inland
     Gulf-Inland Wakulla-Inland Walton-Jackson-Leon-Liberty-
     South Walton-Washington.

GA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for Baker-Ben Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-
     Cook-Decatur-Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-
     Miller-Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-
     Tift-Turner-Worth.

     Heat Advisory from 11 AM to 8 PM EDT Saturday for Baker-Ben Hill-
     Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-Dougherty-
     Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-Mitchell-
     Quitman-Randolph-Seminole-Terrell-Thomas-Tift-Turner-Worth.

AL...Heat Advisory from 10 AM this morning to 7 PM CDT this evening
     for Coffee-Dale-Geneva-Henry-Houston.

     Heat Advisory from 10 AM to 7 PM CDT Saturday for Coffee-Dale-
     Geneva-Henry-Houston.

GM...None.

&&

$$

NEAR TERM...GOULD
SHORT TERM...GODSEY
LONG TERM...HARRIGAN
AVIATION...GOULD
MARINE...GODSEY
FIRE WEATHER...GOULD
HYDROLOGY...HARRIGAN




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.