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FXUS62 KJAX 240812

Area Forecast Discussion
National Weather Service Jacksonville FL
312 AM EST Sat Feb 24 2018


.NEAR TERM...Today and Tonight...

Persistent mean layer 1000-500 mb ridge axis offshore of the SE 
Atlantic coast will shift ESE through tonight which will 
transition steering flow from SSE to SSW with an increase in SW 
tonight as the ridge axis settles across the southern FL 
peninsula. An increase in moisture associated with an easterly 
wave impacting the SE FL Atlantic coast early this morning will 
pivot northward across the peninsula through today, and will bring
an increased chance of showers this afternoon across our FL zones
roughly along and south of a Live Oak toward St. Augustine line 
where low level convergence and diurnal instability will be 
maximized between encroaching sea breezes. Resultant isolated to 
scattered showers will drift back toward the Atlantic coast after 
sunset as SW steering flow increases, with a gradual decrease in 
coverage expected through the night as diurnal instability is 
lost, however, maintained a low 20% chance of showers for most of 
NE FL through the pre-dawn hours Sunday. Refrained from inclusion 
of tstorms today given persist mid level subsidence and dry air 
with mean moisture between 700-500 mb per the GFS40 less than 25% 
which will suppress deep convective growth. 

Early morning fog will become dense at times both today and again
tonight. Dense fog advisories may be needed for portions of the
forecast area. Fog Sat night/Sun morning favored across the Suwannee
River Valley and inland SE GA as low stratus layer advects inland
from the Gulf of Mexico. 

Temperatures will continue to trend near record values, both for 
daytime highs and also for overnight record high minimum 
temperatures. Refer to climate section below for records. 

.SHORT TERM /Sunday and Monday/...

Unseasonable warmth will continue with record max temps likely on
Sunday. Southwest flow will result in the warmest temperatures
occurring along the I-95 corridor both days. An Atlantic 
seabreeze may try to develop on Sunday but if it does it will be 
pinned right at the coast. Beaches should still reach the lower 
80s prior to the development of the seabreeze. No seabreeze on 
Monday as southwest winds increase with breezy conditions expected
at inland locations. Monday should be the warmest day at the 
beaches, with temps possibly reaching the mid 80s. We went above
guidance for max temps both days.

Gulf coast seabreeze will move well inland both days. Isolated 
showers will be possible on Sunday as the seabreeze moves east 
towards the Atlantic coast. A cold front will stall northwest of
the area on Sunday and there is a low chance of showers at areas
west and north of a line from Waycross to Jesup. 

The front will finally get pushed into southeast Georgia late
Monday afternoon and then through northeast Florida Monday night.
A pre-frontal line of scattered showers and possibly a few 
thunderstorms will move into southeast Georgia Monday afternoon.
This activity will weaken and diminish as the upper level energy
gets deflected north of the area. A few showers will be possible
across the Suwannee valley region of northeast Florida, but other
than that, most of northeast Florida will remain dry as the front
moves through Monday night. 

.LONG TERM.../Tuesday through Friday/...

Although temperatures will cool some on Tuesday with northeast
winds in the wake of the front, temperatures will remain above
normal. The coolest readings however will be along the coast with
highs only around 70. 

Winds quickly veer towards the south on Wednesday as a warm front
lifts north. Temperatures will warm back into the upper 70s to
lower 80s with the warmest readings across our southern zones.
Isolated light showers will be possible along the Atlantic coast 
in moist onshore flow along the seabreeze/warm front. A better 
chance for scattered showers will exist across inland southeast 
Georgia in conjunction with the warm front and weak upper level 

Thursday will be windy and warm as southwest flow increases in
advance of the next cold front. This cold front is expected to
move quickly across the area in the Thursday afternoon/evening 
timeframe. There appears to be just enough moisture/forcing to
support at least a few showers along the frontal boundary late
Thursday afternoon and evening. Noticeably cooler/drier air will 
filter into the area with breezy northwest winds on Friday. 



IFR conditions expected to impact the terminals this morning with
highest potential for LIFR or lower at VQQ and GNV. Fog will lift
into low cumulus field by 14Z with VFR conditions expected today.
Potential for restrictions tonight, but confidence in IFR not as
high as previous nights given low clouds and low chances for
showers impacting NE FL terminals late this afternoon into
tonight. Included VCSH at GNV and SGJ after 02Z. 



Prevailing winds SSE 5-10 kts inner waters with 10-15 kts over 
the outer waters today with combined seas 3-5 ft. Dropped the SCEC
headline for the outer waters given observed waves 3.6 ft Greys 
Reef with potential again tonight for elevated SCEC seas as SSE 
winds increase. High pressure will shift SSE of the region today 
through Sunday night ahead of a weakening cold front. This front 
will gradually shift south of the waters Monday into Monday night 
as high pressure strengthens over the Mid-Atlantic region. Onshore
flow will return Tuesday, then winds veer quickly to the south 
Wed as a warm front lifts northward over the waters ahead of a 
stronger frontal system which will impact the waters late in the 
week with the potential for advisory conditions under WNW flow. 

Rip Currents: Moderate risk this weekend. 



Near record max temperatures and near record high minimum 
temperatures expected today through Sunday. 

Record High Maximum Temps for Feb 24th
JAX 88/1962
GNV 88/1962
AMG 85/2012
SSI 84/2012

Record High Minimum Temps for Feb 24th
JAX 68/1962
GNV 65/1909
AMG 66/1996
SSI 63/2017

Record High Maximum Temps for Feb 25th
JAX 85/2001
GNV 85/1962
AMG 83/2001
SSI 80/2017

Record High Minimum Temps for Feb 24th
JAX 66/1883 
GNV 65/2001 
AMG 62/2001 
SSI 62/2017


AMG  86  61  84  61 /  10  10  30  20 
SSI  74  63  79  63 /  10  10  10  10 
JAX  84  65  86  61 /  10  20  20  10 
SGJ  82  66  83  65 /  20  20  20  10 
GNV  86  64  85  60 /  20  20  20  10 
OCF  86  64  85  61 /  30  30  10  10 



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