Severe Thunderstorm Warning 134, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
444 AM EDT Thu Jul 4 2013

...Flash Flooding Remains a Threat Across the Region with an
Isolated Strong to Severe Storms also Possible...

...High Surf and Rip Currents are Expected Along the Coast...

.NEAR TERM [Through Tonight]... Not much change in the wet pattern
for today. The local area resides under deep layer southerly
flow between a deep trough centered over the middle of the country
and a ridge over the western Atlantic. At the surface, essentially
the same pattern exists, with a wave of low pressure south of the
Louisiana coastline and high pressure over the Atlantic. Like
yesterday, the position of the low level wind max within the
gradient between the two aforementioned features, will determine
where the heaviest rain will set up. Unfortunately the ingredients
exist once again for heavy rainfall, with anomalously high PWAT
values, a strong north/south oriented low level jet, and expected
efficient warm rain processes. Expect the heaviest rain bands to
set up west of the Apalachicola and Chattahoochee rivers in areas
that were hit hard yesterday. In these locations expect an
additional widespread 3 to 5 inches today with more localized
higher amounts possibly as high as 10 to 15 inches. Needless to
say this area is rather saturated from yesterday and depending on
where the highest amounts set up, major flash flooding could be
possible. Elsewhere widespread 1 to 3 inch accumulations will be
likely with isolated higher amounts much lower than the
aforementioned areas.

Similar to yesterday, the severe weather potential remains low due
to the lackluster thermodynamic profiles, however cannot be ignored
due the the increased low level shear. Thus, an isolated tornado
cannot be ruled out, as well as isolated damaging winds mixed down
in heavy rainfall. Keep in mind trees may fall easier (in lighter
winds) due to the saturated soils.

&&

.SHORT TERM [Friday Through Saturday]...
The long wave pattern will change little during these periods,
although the trough to our west will begin to weaken a bit by
Saturday. The ridge to the east will be undercut by a TUTT low
which will be approaching the Bahamas by Saturday evening. In
between, the forecast area will remain in deep layer onshore
flow with a steady feed of tropical air into the region. We will
begin to see a gradual downward trend in rain chances across the
eastern zones, especially by Saturday afternoon. However, most of
the area will hold on to likely PoPs which will keep max temps
several degrees below climatology, especially across our western
zones. We could certainty continue to see convergent rain bands
come into the region and with all of the recent and predicted
heavy rain, we may very well need to extend the flash flood
watch out in time to include at least Friday.

&&

.LONG TERM [Saturday Night through Wednesday]...
The upper level trough extending down from the Midwest continues
to deamplify and lift to the northeast allowing the west and east
coast ridge to merge by Monday. The persistent plume of deep layer
moisture will linger over our region through Sunday. At the
surface, high pressure will be centered just east of the mid-
Atlantic states with the axis extending westward through the Lower
Mississippi Valley and north of our CWA. Although a moist
southeast flow will continue in the lower levels, we should see an
intrusion of drier air in the mid- levels Monday through Tuesday.
Deep layer moisture is forecast to return on Wednesday as a
tropical wave moves into the eastern Gulf of Mexico. PoPs will be
tapered from likely (60-70%) west to mid range chance(40%)east on
Sunday. Below climo PoPs (20-40%) for Monday and Tuesday with
seasonal PoPs returning on Wednesday (40-50%). Max temps will be
around 90 degrees with min temps in the lower 70s.

&&

.AVIATION [Beginning 08Z Thursday]...
MVFR to IFR conditions and heavy rain will prevail through much of
the the TAF. A break out to VFR will be possible at KVLD and KABY
where widespread rains may not persist all day. Shower and
thunderstorm coverage will gradually diminish once again later
tonight.

&&

.MARINE...
Low pressure continues to develop over the north central Gulf of
Mexico this morning and small craft advisory conditions are
ongoing across most of the waters. As the low drifts north toward
the coast today, winds and seas will peak. After the low moves
ashore, a gradual diminishing trend will commence with conditions
dropping below advisory levels by Friday morning. A brief return
to cautionary conditions is still forecast for Saturday with
lighter winds and seas expected after that.

Another concern in the near/short term is the ongoing high risk
for rip currents. This risk level was extended east to include
Franklin County and St. George Island. A high surf advisory is now
in effect for Bay and Walton Counties where surf heights could
reach 7 feet today.

&&

.FIRE WEATHER...
Red Flag conditions are not expected in the foreseeable future.

&&

.HYDROLOGY...
The flash flood threat continues across the entire area today,
although it is greatest across the Florida Panhandle and more
marginal the farther east one goes. Additional rainfall amounts of 4
to 8 inches are possible through Friday morning across portions of
the Panhandle. Elsewhere, 3 to 5 inches of additional rain is
expected across southeast Alabama, and 1 to 3 inches is expected
elsewhere. There is still a threat of localized amounts that are
close to double these values, although the greatest threat for major
flash flooding is across the Florida Panhandle.

In terms of rivers, the St. Marks near Newport has risen to moderate
flood stage and is expected to crest near its current level around 9
feet. The Aucilla River near Lamont may also reach minor flood stage
in several days. The Choctawhatchee River is expected to eventually
reach minor flood stage at Caryville and moderate flood stage at
Bruce. We will also need to keep an eye on the Shoal River at Mossy
Head as heavy rainfall expected in Walton county today could
potentially push that river into flood stage as well.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   83  72  87  72  88 / 70  60  70  40  60
Panama City   79  75  85  75  86 /100  70  70  50  70
Dothan        75  71  85  72  87 /100  70  70  40  70
Albany        83  72  87  72  88 / 60  50  70  40  60
Valdosta      89  71  89  71  89 / 80  50  60  40  50
Cross City    88  70  89  71  89 / 60  50  60  40  50
Apalachicola  80  75  85  76  87 /100  70  70  50  70

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...FLASH FLOOD WATCH through Friday morning 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.
     HIGH SURF ADVISORY from 7 AM this morning to 7 AM CDT Friday
     for Coastal Bay-South Walton.
     HIGH RISK FOR RIP CURRENTS through 2 PM EDT /1 PM CDT/ Friday
     for Coastal Bay-Coastal Franklin-Coastal Gulf-Coastal Walton.
GA...FLASH FLOOD WATCH through Friday morning 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...FLASH FLOOD WATCH through Friday morning for Coffee-Dale-
     Geneva-Henry-Houston.
GM...SMALL CRAFT ADVISORY until 11 PM EDT this evening for Coastal
     Waters From Ochlockonee River to Apalachicola Fl out to
     20 NM-Waters from Suwannee River to Apalachicola FL from
     20 to 60 NM.
     SMALL CRAFT ADVISORY until 5 AM EDT Friday for Coastal waters
     from Apalachicola to Destin FL out 20 NM-Waters from
     Apalachicola to Destin FL from 20 to 60 NM.

&&

NEAR TERM/AVIATION/FIRE WEATHER...Harrigan
SHORT TERM/MARINE...Wool
LONG TERM...Barry
HYDROLOGY...DVD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
547 AM EDT THU JUL 04 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 AM     FLOOD            3 WSW NOMA              30.87N 85.66W
07/04/2013                   HOLMES             FL   LAW ENFORCEMENT

            STILL SOME WATER OVER ROADWAYS...INCLUDING SOME LOCAL
            ROADS NEAR HIGHWAY 79.

0545 AM     FLOOD            4 NNE BUNKER            30.44N 86.06W
07/04/2013                   WALTON             FL   LAW ENFORCEMENT

            STILL SOME WATER OVER ROADWAYS...INCLUDING COUNTY ROAD
            3280 NEAR THE FREEPORT AREA...BLACK CREEK BLVD...AND
            FAULKNER DRIVE.

&&

DVD