Flash Flood Warning 111, NWS Jackson, MS

Area Forecast Discussion
National Weather Service Jackson MS
402 PM CDT Fri Oct 25 2019

.DISCUSSION...

Through Saturday...

A rather wet pattern will continue through much of the short term.
Warm front still remains close to the coast with lower to mid 70s
dewpoints remaining in this part of the state. Dewpoints have been
slowly increasing across portions of our forecast area with readings
in the mid 60s. As the low pressure system in the Gulf continues to
move north through the remainder of the afternoon and evening, this
warm front is expected to also move north, bringing a bit more
moisture and instability further inland. Models tend to agree that
this low will move north in the vicinity of the I-55 corridor this
evening and overnight. As it does, the best parameters for strong to
severe storms, including better shear profiles, will be across the
east and southeast parts of Mississippi, potentially reaching as far
west of the I-55 corridor. It is in this region where we previously
expanded both the slight and marginal risks for severe weather. The
main concern will be from damaging winds and tornadoes, coming
roughly from 3am through daybreak. A fly in the ointment may come in
how far north this more unstable air is able to go.

The other concern will be from flash flooding potential. Most
locations have seen steady moderate rain for most of the day with
around 1 to 2 inches common but some locations in the east have seen
amounts upwards of 3 inches. Another 1 to 3 inches will occur
through tonight into tomorrow before all is said and done. Some
rates will be higher/heavier rainfall in convective bands later
tonight into tomorrow and going Flash Flood Watch seems good for
now.

As the surface low deepens and moves inland, given the tightened
pressure gradient, there may be some gusty winds not associated with
more robust convection. Winds will be out of the south/southeast
during the night but will hold off adding anything to the HWO this
afternoon for this threat.

Models continue to quickly push convection out of the region by
early afternoon or perhaps even by noon. Clearly should come
gradually from west to east through the afternoon and evening.
Temperatures have been and will continue to be tricky given rain and
cloud cover. Of course with a northward advancing cold front,
temperatures will remain steady to increase overnight tonight. Highs
tomorrow will roughly be in the 60s and lower 70s. /28/

Saturday night through next week...

A cooler airmass will filter into the region Saturday night
as the surface front pushes east of the region and the upper low
ejects to the north. Some moisture will remain in the lower levels
as surface high pressure increases. Some fog will be possible
throughout the region on Sunday morning. Temperatures will be
slightly below average on Sunday as dry conditions prevail.
Monday will remain dry with temperatures closer to average as the
surface high remains parked over the area.

As with the last several forecast packages, there is still little
agreement amongst guidance moving into midweek. As a trough over
the Rockies deepens on Monday, SW upper flow will begin to
increase over the lower MS River Valley in response. As the
trough begins to migrate eastward on Tuesday, a weak disturbance
embedded in the pattern will help to push a weak front towards the
region. This is where the agreements end.

The GFS still holds on to the drier solution with only light PoPs
in the region on Wednesday into Thursday with cooler air
filtering into the region behind the front. The Euro's solution
continues to be the wetter of the two through the period as a deep
upper closed low crosses the Rockies and approaches the MS River,
keeping rain, storms, and warmer temperatures in the region
through early Friday.

We will continue to lean towards the warmer, wetter midweek
solution due to the performance of the Euro so far in this
transitional season but the forecast remains low confidence until
there is more consensus amongst guidance.

&&

.AVIATION...
18Z TAF discussion:
Not good flying weather expected through much of the TAF period.
Rain and some embedded storms will continue today and sub-VFR
ceilings and vis(most likely in the IFR to LIFR range) will also
prevail. Some storms in the east may bring gusty winds and the
threat for severe weather. Rain will continue tonight into
tomorrow, with clearing coming gradually from west to east
tomorrow afternoon. Until then, IFR to LIFR flight categories
should mostly prevail. Winds will be out of the south southeast
around 10-15kts with gusts up to 25kts. /28/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       65  68  50  71 /  85  72  12   4
Meridian      67  75  50  70 /  91  96  18   5
Vicksburg     61  65  50  71 /  91  57  12   3
Hattiesburg   69  72  50  71 /  90  82  12   4
Natchez       59  63  50  71 /  88  49  12   2
Greenville    60  64  50  68 /  96  60  12   3
Greenwood     63  68  50  69 /  96  76  12   3

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Flash Flood Watch through Saturday afternoon for MSZ018-019-
     025>066-072>074.

LA...Flash Flood Watch through Saturday afternoon for LAZ007>009-015-
     016-023>026.

AR...Flash Flood Watch through Saturday afternoon for ARZ074-075.

&&

JPM3

Hazardous Weather Outlook
National Weather Service Jackson MS
327 PM CDT Fri Oct 25 2019

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>027-034>036-
040>042-047-060-262030-
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Washington-Humphreys-Holmes-
Issaquena-Sharkey-Yazoo-Warren-Adams-
327 PM CDT Fri Oct 25 2019

This hazardous weather outlook is for portions of southeast
Arkansas, northeast Louisiana, central Mississippi, north central
Mississippi, northwest Mississippi, southwest Mississippi, and
west central Mississippi.

.DAY ONE...Tonight and Saturday

FLOODING
THREAT...Elevated
TIMING...Tonight through Saturday

Additional rainfall amounts of 1 to 3 inches with locally higher
amounts will be possible through Saturday afternoon. Flash
flooding is expected.

(https://www.weather.gov/images/jan/graphicast/1.png)

.DAYS TWO THROUGH SEVEN...Saturday night through Thursday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations is not expected through next Thursday.

MSZ028>030-032-033-037-038-043>045-048>050-053-054-059-061-062-
262030-
Montgomery-Webster-Clay-Choctaw-Oktibbeha-Attala-Winston-
Madison MS-Leake-Neshoba-Hinds-Rankin-Scott-Claiborne-Copiah-
Jefferson-Franklin MS-Lincoln-
327 PM CDT Fri Oct 25 2019

This hazardous weather outlook is for portions of central
Mississippi, east central Mississippi, north central Mississippi,
northeast Mississippi, south central Mississippi, and southwest
Mississippi.

.DAY ONE...Tonight and Saturday

FLOODING
THREAT...Elevated
TIMING...Tonight through Saturday

SEVERE THUNDERSTORMS
THREAT...Marginal
TIMING...Tonight

Additional rainfall amounts of 1 to 3 inches with locally higher
amounts will be possible through Saturday afternoon. Flash
flooding is expected.

(https://www.weather.gov/images/jan/graphicast/1.png)

Isolated severe storms will be possible tonight. The main concern
will be from damaging winds and a tornado cannot be ruled out.

(https://www.weather.gov/images/jan/graphicast/2.png)

.DAYS TWO THROUGH SEVEN...Saturday night through Thursday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations may be needed for portions of the region tonight.

MSZ031-262030-
Lowndes-
327 PM CDT Fri Oct 25 2019

This hazardous weather outlook is for portions of northeast
Mississippi.

.DAY ONE...Tonight and Saturday

SEVERE THUNDERSTORMS
THREAT...Marginal
TIMING...Tonight through early Saturday

FLOODING
THREAT...Elevated
TIMING...Tonight through Saturday

Additional rainfall amounts of 1 to 3 inches with locally higher
amounts will be possible through Saturday afternoon. Flash
flooding is expected.

(https://www.weather.gov/images/jan/graphicast/1.png)

Isolated severe storms will be possible tonight. The main concern
will be from damaging winds and a tornado cannot be ruled out.

(https://www.weather.gov/images/jan/graphicast/2.png)
.DAYS TWO THROUGH SEVEN...Saturday night through Thursday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations may be needed for portions of the region tonight
through Saturday.

MSZ039-046-052-058-262030-
Noxubee-Kemper-Lauderdale-Clarke-
327 PM CDT Fri Oct 25 2019

This hazardous weather outlook is for portions of east central
Mississippi.

.DAY ONE...Tonight and Saturday

FLOODING
THREAT...Elevated
TIMING...Tonight through Saturday

SEVERE THUNDERSTORMS
THREAT...Slight
TIMING...Mainly Tonight

Additional rainfall amounts of 1 to 3 inches with locally higher
amounts will be possible through Saturday afternoon. Flash
flooding is expected.

(https://www.weather.gov/images/jan/graphicast/1.png)

Severe storms will be possible tonight. The main concern will be
from damaging winds and tornadoes.

(https://www.weather.gov/images/jan/graphicast/2.png)

.DAYS TWO THROUGH SEVEN...Saturday night through Thursday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations may be needed for portions of the region tonight
through Saturday.

MSZ051-055>057-063>066-072>074-262030-
Newton-Simpson-Smith-Jasper-Lawrence-Jefferson Davis-Covington-
Jones-Marion-Lamar-Forrest-
327 PM CDT Fri Oct 25 2019

This hazardous weather outlook is for portions of central
Mississippi, east central Mississippi, south central Mississippi,
and southeast Mississippi.

.DAY ONE...Tonight and Saturday

FLOODING
THREAT...Elevated
TIMING...Tonight through Saturday

SEVERE THUNDERSTORMS
THREAT...Slight
TIMING...Tonight

Additional rainfall amounts of 1 to 3 inches with locally higher
amounts will be possible through Saturday afternoon. Flash
flooding is expected.

(https://www.weather.gov/images/jan/graphicast/1.png)

Severe storms will be possible tonight. The main concern will be
from damaging winds and tornadoes.

(https://www.weather.gov/images/jan/graphicast/2.png)

.DAYS TWO THROUGH SEVEN...Saturday night through Thursday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations may be needed for portions of the region tonight.

28

&&

...HAZARD LEGEND...

*FLOODING*
Extreme...Confident in significant flooding.
Significant...Significant flooding possible.
Elevated...Confident in flooding.
Limited...Flooding possible.

*SEVERE THUNDERSTORMS*
High...Significant severe thunderstorms are expected.
Moderate...Severe storms expected with significant
 severe weather possible.
Enhanced...Severe storms expected.
Slight...Severe storms possible.
Marginal...Isolated severe storms possible.

...USEFUL WEATHER WEB PAGES (URLS)...

NWS JAN Home page...
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Stay Aware, Stay Safe NWS JAN Briefing Page...
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Latest Weather Briefing...
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...ADDITIONAL URLS FOR FLOODING ISSUES...

Current Watches and Warnings...
   https://www.weather.gov/jan/safe_HeavyRain

Observed Precipitation Images...
   https://www.weather.gov/jan/precipmaps

River Forecast Center...
   https://www.weather.gov/lmrfc/
Significant River Flood Outlook...
   https://www.wpc.ncep.noaa.gov/nationalfloodoutlook/index.html
Day 1 through 3 Excessive Rainfall...
   https://www.wpc.ncep.noaa.gov/qpf/excess_rain.shtml
Excessive Rainfall Discussion...
   https://www.wpc.ncep.noaa.gov/discussions/qpferd.html
Day 1 through 7 QPF...
   https://www.wpc.ncep.noaa.gov/qpf/qpf2.shtml
QPF Discussion...
   https://www.wpc.ncep.noaa.gov/discussions/qpfpfd.html
...ADDITIONAL URLS FOR SEVERE WEATHER ISSUES...

Storm Prediction Center (SPC)...
   https://www.spc.noaa.gov/
Meso Analysis...
   https://www.spc.noaa.gov/exper/mesoanalysis/
Day 1 through 3 Outlooks...
   https://www.spc.noaa.gov/products/outlook/
Storm Reports...
   https://www.spc.noaa.gov/climo/online/