Scientific Forecaster Discussion
fxus64 kjan 160857
Area forecast discussion
National Weather Service Jackson MS
357 am CDT Mon Sep 16 2019
Today and tonight: early morning water vapor imagery/rap analysis
showed the circulation around a 592dam high centered over the
Central Plains with a couple of features rounding this high that
will affect our weather today. The first feature noted was a weak
shortwave dropping over north Mississippi that will help draw drier
air south into our County Warning Area as it continues tracking east through tonight.
The second feature was a mid/upper level low tracking west in the
northwest Gulf of Mexico. This feature will aid convection south of
our County Warning Area that model consensus suggest may spread north to the Highway
84 corridor this afternoon. Early morning surface analysis had an
1020mb high centered over the Appalachians that will ridge back to
the west across our County Warning Area and maintain a dry east low level flow.
Ridging surface and aloft will lead to another warmer than normal
day and dry for all except our southern most zones where low chances
of a few isolated storms will be carried this afternoon. Any storms
that develop are expected to dissipate early this evening.
Temperatures will top out in the mid to upper 90s which will lead to
peak heat index values around 100f, especially in the west where the
highest temperatures are expected. Mostly clear skies, light winds,
and warmer than normal temperatures will be the rule again tonight.
Tuesday into the weekend...hot and mainly dry conditions will
continue through the rest of the work week as a steep and stagnant
upper ridge remains parked over the Mississippi River valley.
Highs on Tuesday through Thursday will remain well above their mid
September averages, approaching triple digits and record values
each day at some locations. Although there is continuing
confidence of temperatures in the upper 90s, the dry surface
airmass and afternoon mixing will help to keep heat indices below
the 105 degree threshold for any significant period of time.
Pwats will remain between 1.25" and 1.75" with the highest values
occuring in the southwest portions of the region. Consequently, the
southwestern portions of the region will see the best chances of an
isolated storm or two. Rain chances will begin to slightly increase
as temperatures begin to slightly decrease as we get closer to the
weekend and the upper ridge begins to slowly lose influence over our
weather pattern. Global model solutions begin to drag a front close
to the region late in the weekend/early next week but begin to fall
beyond the scope of reasonable consensus during this period.
On a climatic note, the coolest high temperature we've seen at kjan
over the first 15 days of September has been 93 degrees with an
average high of 96 degrees. To put this in perspective, the average
high on September 1st is 90 degrees. We haven't experienced a day
with a high below 90 degrees since August 26th and none are
forecasted for the 7 days.
06z taf discussion:
VFR conditions will prevail through Monday night. /22/
Preliminary point temps/pops...
Jackson 96 71 98 72 / 4 0 2 2
Meridian 96 68 98 70 / 3 0 1 2
Vicksburg 98 70 99 72 / 5 1 3 3
Hattiesburg 94 71 98 72 / 13 1 5 4
Natchez 95 72 95 72 / 12 3 9 6
Greenville 97 70 98 72 / 2 0 2 2
Greenwood 96 70 98 71 / 1 0 2 3