AREAS OF DENSE FOG TONIGHT...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ON MONDAY FOR
SOUTHEAST ALABAMA AND SOUTHERN GEORGIA....
NEAR TERM [Rest of Today into Tonight]...
The large scale longwave pattern remains relatively amplified yet
progressive. This is highlighted by ridging over Wrn states, broad
trough Ewd to Ern seaboard and H5 ridge ridge now shunted offshore
into Wrn Atlc. Within the troughing centered from Rockies across
great plains, a series of shortwaves will continue to translate
rapidly Ewd shifting trough Ewd and serve as focus of weather. Each
of these shortwaves will eject NEWD and weaken as they try to phase
together to sharpen trough. One shortwave is progged to reach Cntrl
IL, another to WRN TN, another to SRN High Plains by sundown and yet
another that raced NEWD over AL and began to interact with the
frontal system and deep layer moisture. High clouds ahead of
trough/shortwave streaming across Gulf region.
At the surface, low over Great Lakes with trailing cold front SSW
to low near Memphis then quasi-stnry across AR and SE TX with a line
of showers and thunderstorms within area of H85 convergence from Ern
TN swwd into sern TX. Marine warm front observed from SE TX ENE
across AL/FL Panhandle. This cold front has shunted high pressure
center into the extreme Wrn Atlc with veering winds and higher dew
points that allowed dense fog this morning to linger areawide.
Tonight, the trough will weaken, still the combination of a strong
sub-tropical jet S/E of upper trough combined with passing
shortwaves embedded in jet will reamplify trough providing stronger
lift into LWR MS Valley with increasing onshore Gulf flow
overspreading Ewd and eroding local high. All this should bring an
increase in shallow isentropic induced showers and possibly a few
tstms will begin over the Gulf assocd with lifting warm front and
move inland ahead of a larger area of more widespread convection
moving in from the NW assocd with approaching trough/shortwave/cold
front. Will go with 60-0% NW-SE pop gradient. All VSBY guidance
imply areas of a dense and locally widespread fog mix of
radiation and advection fog. this reflected in GRIDS and a Dense
Fog advisory may be needed tonight.