FXUS64 KJAN 220843

Area Forecast Discussion
National Weather Service Jackson MS
343 AM CDT Sun Jul 22 2018

Today through Tonight: The primary concerns will be elevated heat
stress and Isolated strong storm issues for the period.

Latest rap and satellite analysis continued to show the ridge trough
pattern over the conus. This was characterized by anomalous mid to
upper ridging over the Rockies to the Southern Plains as well as
troughing over the eastern conus. Anomalous low level temps will
bring another hot day to the region. With dewpoints well into the
70s we can expect highs from the lower to upper 90s across central
Mississippi along with lower 100s across the MS River in southeast
Arkansas and Northeast Louisiana. This will add up to heat indices
from 105 to around 110 degrees. Expect Heat Advisory criteria to be
meet during the day. So will continue the advisory from late morning
to early evening across mainly the western half of the forecast area
where heat indices will be from 105 to 110 degrees.

Area radar showed isolated strong storms affecting the delta region
overnight. During the day expect the airmass across the west to be
more stable due to the activity overnight into the early morning
hours. Latest CAM guidance shows that isolated strong storms will
affect our eastern counties in northwest flow aloft later today. The
main risk will be damaging winds and up to quarter sized hail
generally from 4 to 9 pm. In the east vertical totals will be in the
lower 30s, decent lapse rates, and 0-3km shear around 35 knots will
provide a favorable airmass. Expect the best limited coverage of
storms to be in the east. Expect the storms to wane during the
overnight hours with lows mainly in the middle 70s./17/

Monday through Saturday: by Monday morning a cooler and drier
airmass will be over our CWA thanks to a large nearly stacked low
centered over the Ohio valley. PWATs wl be less than an inch and a
half with surface dew points in the upper 60s over much of our CWA.
The exception will be our southwest most zones where greater
moisture will reside close to a stalled frontal boundary. Normal
afternoon highs run in the lower 90s. Highs Monday will range from
the upper 80s northeast to lower 90s elsewhere. Normal lows run in
the lower 70s. Tuesday morning is expected to be the coolest morning
of the week with sites across the northern half of our CWA bottoming
out in the upper 60s, with lower 70s expected south. Models remain
in good agreement that the nearly stacked low will drift south
through Tuesday becoming centered over the Alabama/Georgia state
line before weakening into an upper level trough Wednesday and
lifting northeast of the region Thursday. Wl remain on the west side
of the trough axis resulting in very little chance for rain through
mid week which will be limited to east Mississippi. By Thursday the
mid level trough will have lifted northeast of our region while
another closed low tracking east across Manitoba into Ontario helps
send an associated cold front south towards Mississippi. Heat and
humidity will build back across our area through Saturday ahead of
the approaching cold front. This will lead to a return to more
diurnal rain chances each day. It will also lead to higher peak heat
index values. As temperatures top out in the mid to upper 90s over
our western most zones Friday, peak heat index values will approach
105F again. Peak heat index values will approach 105F over more of
our CWA Saturday as afternoon highs reach the mid 90s over most of
the area. The caveat Saturday is that a greater coverage of storms
is expected which may offset the anticipated heat. The cold front
looks to remain north of our CWA through Saturday night. /22/


06Z TAF discussion:
VFR conditions can be expected through the period. A weak front
will come across the region and provide winds of 10 to 15 knots
from the north during the day before becoming light north during
the evening./17/


Jackson 94 69 92 70 / 3 2 3 3
Meridian 94 70 89 68 / 6 1 10 10
Vicksburg 97 72 92 68 / 1 5 4 1
Hattiesburg 98 71 93 71 / 10 5 8 9
Natchez 100 74 91 69 / 1 9 9 4
Greenville 94 69 90 68 / 1 1 3 1
Greenwood 92 69 89 67 / 2 1 3 3


MS...Heat Advisory from 10 AM this morning to 8 PM CDT this evening
for MSZ053-054-059>065-072>074.

LA...Heat Advisory from 10 AM this morning to 8 PM CDT this evening
for LAZ015-016-023>026.




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