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fxus64 kjan 250641 
afdjan

Area forecast discussion
National Weather Service Jackson MS
141 am CDT sun Aug 25 2019

Update...
updated for 06z aviation discussion

&&

Aviation...
06z taf discussion:
rain showers continues across portions of the area this morning but should
gradually diminish through the night. With some brief
daybreak/early morning MVFR or lower stratus, VFR conditions
should resume by mid-morning. Rain showers/thunderstorms and rain looks to affect much of
the area today, most likely many taf locations. However, opted to
return to thunderstorms in the vicinity for now before better timing can be pinpointed in
future forecasts. Thunderstorms and rain should be mostly confined to 17z-01z across
the area with some diminishing through the night. /28/

&&

Discussion...
showers and storms continue this evening across mainly northern
portions of the area in the vicinity of a stalled frontal boundary.
For the overnight, expect a decrease in coverage of showers and
thunderstorms with the loss of daytime heating, but there could be
some isolated activity through the overnight. Lows will mainly be in
the lower to middle 70s. No major changes were needed to the
forecast. /27/

Prior discussion below:

This afternoon through tomorrow:

As evidenced by the measured precipitable water value of 2.17 inches on our
local sounding this morning, abundant moisture is in place across
our region. A weak low pressure system over the Texas/la coastline
this afternoon continues to organize a few bands of showers and
thunderstorms moving across southwestern portions of our area. An
area of subsidence on the edge of this system appears to be
limiting convection somewhat from near Cleveland, MS southeast
toward Hattiesburg, MS this afternoon, but another area of showers
and storms associated with a stalled frontal boundary is
affecting the Golden Triangle and Meridian areas. As we head into
the overnight hours, expect a general decrease in coverage of
showers and thunderstorms with the loss of daytime heating, but
the low pressure system to our southwest and an approaching
shortwave from the northwest should provide enough synoptic
forcing to keep at least some showery activity ongoing through
the night.

Weak steering flow today (850-200mb wind < 10kts) will result in the
potential for some locally heavy downpours, but expect increased
flow (850-200mb wind near 20kts) by tomorrow as the shortwave dips
into our region. Given better flow and better synoptic support,
went ahead and matched MOS guidance "likely" pops across the area
tomorrow. Deep moisture will remain in place and heavy downpours
will remain possible, but given the increasing flow for tomorrow,
will hold off on including any limited flood potential in the
hazardous weather outlook text or graphics at this time. /Nf/

Sunday night through wednesday:

A wetter than normal pattern will continue as mean troughing
builds over the eastern Continental U.S. Into early next week and a rather
moist airmass remains entrenched across the region. Sunday night
into Monday, what's left of the tropical wave loitering along the
la/Texas coast will begin to lift northeastward across the area,
maintaining higher rain chances even during the overnight hours.
With precipitable water projected in the 2-2.5" range and some guidance hinting at
training convection, localized flash flooding may become a
concern. There is still a bit too much uncertainty with respect to
location to highlight a particular area in the severe weather potential statement/graphics, but
it remains a threat we will monitor in the coming days. After a
brief lull in activity behind this system, a cold front will
approach the region later Tuesday into Wednesday. Richer deep
moisture will again pool across the area ahead of the front,
keeping higher rain chances going through midweek. Temperatures
will be near to slightly below normal during this time frame, and
of course, will be modulated by the nuance of daily cloud/rain
coverage.

Thursday through next saturday: confidence is increasing in a cold
front moving through the area late Wednesday or early Thursday, with
noticeably drier air moving into the region. Overnight temperatures
in the 60s will be common, and in spite of daytime temperatures in
the upper 80s to near 90, with the drier airmass it will feel rather
pleasant (at least comparatively). Just beyond this time frame, rain
chances may begin to sneak back up due to a resurgence of tropical
moisture. /Dl/

&&

Preliminary point temps/pops...
Jackson 88 71 87 73 / 76 61 65 22
Meridian 90 72 85 72 / 81 68 74 31
Vicksburg 87 74 89 75 / 82 49 54 21
Hattiesburg 88 71 87 72 / 76 63 74 21
Natchez 84 72 87 74 / 84 48 61 15
Greenville 88 72 88 74 / 74 53 51 14
Greenwood 88 72 86 73 / 78 62 57 23

&&

Jan watches/warnings/advisories...
MS...none.
La...none.
Arkansas...none.

&&

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