Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus64 kjan 140908 

Area forecast discussion
National Weather Service Jackson MS
408 am CDT Mon Oct 14 2019

today through Tuesday night:

Stalled warm front under perturbed flow aloft will help rain
chances gradually increasing through the afternoon across the
region, especially tonight & through Tuesday. Synoptic pattern
this morning consists of a deep mid-level ridge that will continue
to build over the western Gulf of Mexico. The stationary front is
parked across the northern Gulf & along the Gulf Coast. With
increasing moisture advection & isentropic ascent over the top of
this baroclinic zone, expect deep layer moisture to gradually
increase from the southwest through the day. This will help nearly
2+ inch pws to increase across areas south of I-20. Expect
scattered light-moderate rain showers to gradually increase from
the south, especially in southwest Mississippi & along the
Mississippi River. Due to continued warm air advection, we still
should warm above near normal today but showers & clouds could
keep areas south of I-20 down somewhat.

The best ascent will come tonight through Tuesday as isentropic
ascent & A Reservoir of deep tropical moisture moves in tonight
through Tuesday. Pws will approach 2.25+ inches & low-level
Theta-east approaching 340k. There remains considerable potential for
heavy pockets of rainfall, right along the I-20 corridor but there
still is some uncertainty on how far south that axis will situate.
Due to the Euro consistently placing some higher rainfall totals
generally south of I-20, this still keep enough uncertainty to
pull the axis slightly south. This somewhat removes some of the
Highway 82 corridor but introduces slightly more of the Highway 84
corridor in the "limited" for flash flooding. 2-4 inches still
remains possible, with some locally higher amounts approaching 5
inches possible. Due to that, there may be some potential for a
potential upgrade in the severe weather potential statement as spatial details are ironed out. In
addition, there remains fast westerly flow aloft for some
juxtaposition of parameter space for some more organized, stronger
storms. There still remains considerable uncertainty, due to such
a sharp gradient in convection & destabilization, how much will
develop more in the warm sector. Will continue to keep out of the
severe weather potential statement for now but will have to keep a close eye on it as we get
closer. A risk area for some isolated severe storms may be
warranted for areas generally along the Highway 84 corridor if
model consensus trends in that direction. As the mid-level system
swings through, there will be somewhat of a decrease in
convection coverage into Tuesday night, with a somewhat of a brief
uptick from increasing ascent along a digging synoptic trough &
approaching cold front. With decreasing low-deep layer moisture,
showers will be on the decrease across the Delta while some will
reside across the Pine belt before the front swings through. Lows
will be generally above normal southeast of the Natchez trace,
due to rain & clouds, while near normal across the Delta in the
wake of the front. /DC/

Wednesday through sunday: dry weather will be returning to the
region Wednesday as the cold front moves out of the region, and high
pressure builds in. Expect dry weather Thursday and Friday as high
pressure remains in control. The next storm system will move out of
the plains into the MS valley by the weekend, with the old front
coming back north Saturday leading to a few showers for the weekend.

High temperatures Wednesday and Thursday will generally range from
the mid 60s north to the mid 70s south. Lows Wednesday and Thursday
nights will in the 40s north/central, to around 50 across the south.
Highs will be warming back into the 80s for most locations for the
weekend. /27/


06z taf discussion:
MVFR ceilings will be possible by around 09z Monday morning for
most sites, with fog possible at gwo/glh/gtr. Rain showers coverage will
be increasing from the southwest Monday afternoon, and should
begin to affect Jan/hks/mei/hbg/pib around 14/21-22z. Conditions
look to be approaching IFR for mainly southern sites as more
significant rain moves in around 15/00-02z. /27/


Preliminary point temps/pops...
Jackson 76 66 75 63 / 26 87 92 78
Meridian 75 65 75 65 / 18 87 94 81
Vicksburg 78 66 76 62 / 33 87 91 78
Hattiesburg 75 68 82 69 / 33 51 78 71
Natchez 74 67 81 64 / 58 55 83 78
Greenville 76 64 71 56 / 9 82 92 54
Greenwood 76 64 70 57 / 7 75 90 58


Jan watches/warnings/advisories...


National Weather Service Glossary of Abbreviations