Severe Thunderstorm Warning 18, NWS Jacksonville, FL

Area Forecast Discussion
National Weather Service Jacksonville FL
258 PM EDT Mon Apr 9 2018

...Locally heavy rainfall across North Florida through Tuesday
Night...

.NEAR TERM /through Tuesday/...
Band of showers/isolated thunder continues along and just N of
east-west warm frontal boundary that is forecast to remain over
north-central FL through Tonight. Latest guidance suggests one
wave of showers/isolated thunder moves across nctrl FL into ne FL
late afternoon into early evening. Another wave of heavier
showers/isolated thunder is forecast to affect nctrl FL later
Tonight, with scattered showers further north due to weak
isentropic lift north of the warm front. Some increase in coverage
seen toward 12z particularly I-10 northward and hourly POPs
increase accordingly. Temps won't drop very much in warm advection
pattern. Latest consensus guidance similar to our current low
temp forecast, with mid 50s across se GA, 55-10 I-10
corridor...lwr 60s further S and coast except perhaps mid 60s
southernmost counties.

A cloudy wet day is forecast for Tuesday. Rainfall expected to be
most widespread, and heaviest, SE of GNV-JAX line. Could see
areas with 2-3 inches of rain there thru Tuesday. Isolated to
scattered t-storms anticipated especially S of I-10 corridor.
Latest consensus guidance has high temps only lwr-mid 60s se GA,
mid 60s I-10 corridor, 65-70 GNV-SGJ, and 70-75 further south.

.SHORT TERM /Tuesday Night through Thursday/...

Tuesday Night...Low develops on front East of JAX over the Atlc
Coastal Waters and pulls trailing frontal boundary slowly
southward through the FL peninsula and offshore. This will still
allow for locally heavy rainfall and embedded storms across NE FL
during the evening hours, then rainfall slowly ending after
midnight with clearing skies from the NW across SE GA after
midnight and NE FL towards morning. Cooler temps will filter in by
Wed Morning with mid/upper 40s across SE GA/Suwannee Valley and
lower to middle 50s along the coast and the rest of NE FL.

Wed-Thu...High pressure builds north of the region on Wednesday
then pushes offshore on Thursday. Mostly Clear with slightly
cooler than normal temps are expected in the NE flow on Wednesday
with highs in the 70s inland and upper 60s at the coast, then near
normal temps on Thursday in the SE Flow as highs near 80 degrees
inland and lower/middle 70s at the coast. Cool overnight lows in
the upper 40s/lower 50s inland Wed Night and mid/upper 50s at the
coast.

.LONG TERM /Friday through Monday/...
Long-range models in good agreement for next frontal passage to
impact the area on Sunday with showers/isolated storms, while
above normal temps are expected ahead of this on Fri/Sat as mild
southerly flow pushes Max Temps into the lower/middle 80s. Cooler
and drier airmass expected on Monday following the frontal passage
with below normal highs in the 60s/lower 70s. Winds will be breezy
out of the S-SW at 15-25mph on Sat/Sun, then breezy W-NW flow on
Monday.

&&

.AVIATION...CIGS have increased into MVFR range early this
afternoon. Have maintained this in TAFs thru the afternoon...then
showing decrease to IFR range Tonight as showers and isolated TSRA
increase across the area. Best chance of TSRA appears to be
KGNV/KSGJ, and included TSRA for those sites.

Expecting IFR to low-end MVFR conditions through much of the day
Tuesday with occasional showers.

&&

.MARINE...A warm front will stall across the Fl waters this
afternoon and Tonight. Winds will be generally NE across the
GA waters and light and variable FL waters. A wave of low
pressure will move along front over the waters Tuesday, bringing
widespread showers and thunderstorms. Northerly winds will
increase behind the low. Winds could approach advisory criteria
particularly over the offshore component Tuesday afternoon thru
Wednesday. Conditions will improve Thursday and Friday as high
pressure builds over the waters.

Rip Currents: Low risk this afternoon due to lighter winds.
Moderate risk expected Tuesday as onshore flow and swells
increase.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  54  63  46  75 /  60  60   0   0
SSI  55  62  52  69 /  60  70  20   0
JAX  59  65  51  73 /  70  70  40   0
SGJ  62  68  54  71 /  70  80  70   0
GNV  62  70  51  77 /  80  80  50   0
OCF  65  74  53  78 /  80  80  60   0

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&

Wolf/Hess