Area Forecast Discussion
Issued by NWS Jackson, MS
FXUS64 KJAN 250218 AAA
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
918 PM CDT SUN JUL 24 2016
.UPDATE...Expecting remaining shower and storm activity this evening
to have dissipated by midnight based on latest trends and guidance.
Lows tonight will be in the low to mid 70s. As for the current
forecast, lowered pops later tonight to remove precip, and adjusted
the hourly temps for this evening to account for the latest trends.
.AVIATION...Isolated thunderstorms will linger over the area
until 25/04Z, otherwise MVFR visibilities in fog will develop and
linger through 25/14Z. Scattered thunderstorms will be seen once
again Monday after 24/18Z./26/
.PREV DISCUSSION... /issued 352 PM CDT SUN JUL 24 2016/
DISCUSSION...It has been another muggy day, albeit not terribly
hot, across the ArkLaMiss region. Convection was ongoing early this
morning in association with an upper low/shortwave across the
region. This, combined with dewpoints in the 70s/PW values exceeding
two inches, and increasing daytime heating, resulted in further
coverage of showers and storms this afternoon. The greatest
concentration of storms continues to be in western counties/parishes
and overall these locations have seen about 1.5 to 3 inches in
spots. Most of these storms remain below strong or severe thresholds
as lapse rates today remain rather meager. However, it isn`t out of
the realm of possibility for one or two to bring some gusty winds.
The primary concern with these storms will be from frequent
lightning and heavy downpours. Further east, additional storms have
developed but coverage is more isolated to scattered.
The development of clouds and rain has kept temperatures closer to
or below normal for this time of year. This has limited heat indices
as well despite dewpoints in the mid 70s. Even still, some locations
have observed heat indices of 100 to 105 degrees, with isolated
spots exceeding 105 degrees(this is primarily in the heat advisory
region). Was thinking about canceling the heat advisory early due to
the considerable rain and cloud coverage, but some locations within
the advisory area have been spared some of the heavier rainfall and
seen some better insolation and thus will keep the advisory going. We
will, however, let it expire this evening.
The aforementioned low/shortwave will continue to track west and
this convection should diminish with the loss of daytime heating.
Continued muggy conditions will occur overnight and again on Monday.
A TUTT low, currently over south Florida, will track westward across
the Gulf of Mexico tomorrow and into Tuesday. This, combined with
continued moisture over the region(as characterized by PW values
around 2 inches in the western and southern part of the forecast
area), will bring another afternoon of decent coverage of storms on
Monday, despite meager output from hi-res models. Models do show
some drier air moving in from the east in association with this TUTT
low, but there should still be enough moisture to bring some
potential for storms further north and east. Some models indicate
that dewpoints may mix into the upper 60s, which certainly would
feel much better, but may allow temperatures to heat more. Given
more rain and clouds in the central and west, temperatures will not
have the potential to get warm again tomorrow so heat issues are
again a little more questionable. Kept the limited heat potential in
the west going for Monday primarily for the better dewpoints, but
could certainly see this not panning out as well. These locations
should still see heat indices around 100-105 degrees. No heat
advisory is expected for tomorrow.
Continued high rain chances will remain in the forecast due to our
location within a weakness in the upper ridging pattern. This
pattern will also keep temperatures closer to normal for late July.
There may be some more heat issues later in the week due to moisture
increasing back again as PW values increase again to around two
.PRELIMINARY POINT TEMPS/POPS...
Jackson 74 94 74 92 / 30 27 20 38
Meridian 74 95 73 95 / 16 26 20 32
Vicksburg 75 94 74 93 / 29 29 20 36
Hattiesburg 74 91 72 89 / 18 46 20 55
Natchez 73 91 73 89 / 34 48 20 48
Greenville 75 94 74 94 / 24 27 20 22
Greenwood 73 94 73 93 / 23 26 19 22