730 
FXUS62 KTAE 130307
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1107 PM EDT Fri Jul 12 2013


.NEAR TERM [Through Tonight]...
Other than some adjustments to PoPs with some fairly strong storms
lingering well after sunset, current fcst is essentially on track
and only additional minor tweaks to the current package were made. 

&&

.SHORT TERM [Saturday Night Through Sunday Night]...
This promises to be a complex forecast due to a very atypical 
pattern we have setting up over the CONUS. An upper level low in the 
vicinity of the OH/WV border is dropping southward toward eastern KY 
this afternoon, but will begin to retrograde westward tonight and be 
positioned over eastern KS by Sunday. After that, the system will 
drop southward into the Southern Plains. Surface analysis shows a 
northeast to southwest oriented trough bisecting our forecast area. 
The tricky part of the forecast involves the development of a closed 
circulation on this trough and where it moves once formed. There is 
now a general model consensus that low pressure will develop over 
the northeast Gulf of Mexico and if it does, it will be pulled 
closer to the coast as the upper system gains longitude and pulls it 
northward. It appears at this time that a closed circulation can be 
deduced from satellite imagery and buoy data just southeast of the 
mouth of the Mississippi River. We therefore chose to go with the 
more westward cyclogenesis depicted in the GFS. This model then 
draws the low northwestward toward the Mississippi coast on Sunday. 
The take away here is that there is a lot of uncertainty in the 
forecast and that winds could change considerably over what is 
issued today. Regardless of where the low develops, it does appear 
more certain that a high PoP forecast remains in order. Drier air 
aloft will initially keep PoPs lower across our western zones, but 
likely PoPs are expected for most areas with categorical for the 
eastern FL Big Bend counties on Saturday.

&&

.LONG TERM [Monday through Friday]...
By the start of this period, the upper low will have retrograded all 
the way to the Southern Plains with a large upper high centered over 
Ohio ridging southward to the Northeast Gulf of Mexico. The surface 
ridge will be displaced a bit to the east of the upper feature, but 
will still ridge into our area. The deep layer ridging would 
normally suppress convection below typical summertime levels. 
However, a series of easterly waves will work their way across the 
FL Peninsula during this time and keep PoPs closer to normal. It 
should be noted that the NAM brings a tropical cyclone to the east 
coast of FL by Monday evening and is being discounted in favor of an 
open wave. Temps will be close to normal overnight and a couple of 
degrees below normal during the afternoons.

&&

.AVIATION ...  
[Through 00 UTC Sunday] The Hi-Res models were not very aggressive
at all with flying restrictions overnight tonight, but this could
change with early evening rainfall after sunset. For this package,
just went with MVFR at DHN, ABY, and VLD, but TLH may need to be
amended later tonight with 0.29" of rain falling after sunset.

&&

.MARINE...
This forecast will be subject to some substantial modifications over 
the next 24 hours as we await the development of low pressure over 
the northeast or north central Gulf of Mexico. At this time, we 
anticipate a low developing southwest of the waters tonight and 
lifting northwestward toward Mississippi on Sunday. Other models 
have the low developing further east over the forecast waters. If 
this happens, the forecast will need to be updated. As it stands 
now, we are calling for exercise caution conditions to develop over 
the western legs on Saturday and continuing through the weekend. 
During the upcoming work week, high pressure will build north of the 
waters setting up an easterly flow regime with surges of wind to 
near cautionary levels during the overnight and morning hours.

&&

.FIRE WEATHER...
Red Flag conditions are not expected for some time. 

&&

.HYDROLOGY...
All river points that have been in flood continue to recede,
albeit slowly on the lower Choctawhatchee, where
Caryville and Bruce will remain at flood stage for some time.
Routed flows from the Withlacoochee and Alapaha Rivers are
progressing downstream and are now beginning to initiate rises in
the lower portions of these rivers and into the Middle Suwannee.
There is considerable capacity in the Suwannee Basin, so barring
significant rainfall, flooding is not anticipated along the Middle
Suwannee, though flows may approach action stage by the middle of
next week at Ellaville and Dowling Park. It is helpful that routed
flows from the Upper Suwannee remain relatively low, as the bulk
of the expected rise on the Middle Suwannee is occurring from the
Withlacoochee and Alapaha Rivers.

The rainfall over this weekend is expected to average aerially 
around 2 to 3 inches, with isolated heavier totals possible. This 
certainly does not look to be like the significant flooding 
rainfall we saw last week, and as a result, widespread flooding is 
not anticipated. However, given the wet soil conditions across much 
of North Florida and Southern Georgia, a couple of inches of rain in 
a short amount of time could easily generate localized flooding, 
especially in an urban environment. Expected rainfall could keep 
rivers currently in flood at those levels well into next week (like 
the Choctawhatchee) and could result in basins like the Ochlockonee 
or Chipola nearing flood stage depending on the location of the 
heaviest rains.


&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   72  84  72  89  72 / 60  70  40  60  40 
Panama City   73  85  74  86  75 / 50  60  30  50  40 
Dothan        72  84  71  85  72 / 60  60  30  50  30 
Albany        73  84  72  89  72 / 40  70  40  60  30 
Valdosta      72  88  72  91  72 / 70  80  40  60  30 
Cross City    71  88  72  89  71 / 60  80  40  60  30 
Apalachicola  72  83  73  88  75 / 50  70  40  50  50 

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.

&&

$$

NEAR TERM...Gould
SHORT TERM...Wool
LONG TERM...Wool
AVIATION...Gould
MARINE...Gould/Wool
FIRE WEATHER...Harrigan 
HYDROLOGY...Godsey