Alert archive / Mississippi / Special Weather Statements in 2021

Special Weather Statement, NWS Jackson, MS

September 1, 2021Lowndes County, Mississippi

NWS Jackson, MS issued this special weather statement at Sep 1, 2021, 1:03 PM CDT for Lowndes County, Mississippi. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 1, 2021, 1:03 PM CDT (18:03 UTC)
Expired
Sep 1, 2021, 1:45 PM CDT
In force
42 min
Issued by
NWS Jackson, MS
Hail
0.00 in
Wind
50

County Lowndes County, MS

The radar

The Columbus AFB radar (KGWX), 28 km from the middle of the area, began a volume at 18:05 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 6.1 hours before the alert went out and 156 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 2021-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 170 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 12:00Z on 2021-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
170 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
990 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Jackson, MS wrote its last area forecast discussion before this special weather statement went out at Sep 1, 12:49 PM CDT, 14 minutes earlier.

Area forecast discussion, Sep 1, 12:49 PM CDT, 14 minutes before
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1249 PM CDT Wed Sep 1 2021

.UPDATE...
Updated for 18Z aviation discussion

&&

.AVIATION...
18Z TAF discussion:
VFR conditions prevail across the area this afternoon. Scattered
SHRA/TS will develop and move across the region ahead of a cold
front late this afternoon through this evening, with brief
categorical reductions possible in localized +RA. Early Thu
morning to around daybreak, brief patchy fog development is
possible again, mainly across south MS and central LA. Otherwise,
VFR conditions will continue. /DL/

&&

.DISCUSSION...
Mostly sunny and humid conditions exist across the area this
morning, save for a small portion of south MS with pesky low
stratus. A cold front is now pushing southward into north
AR/northwest TN/MO Bootheel and will continue across the Mid South
today. Ahead of the front, a cluster of convection has moved
southeastward through the Memphis area this morning and is on
track to move into the Golden Triangle and east MS by early
afternoon. Though this activity is currently outflow-dominant, it
is within a region of 20-25 kt of effective bulk shear and around
2000 J/kg MUCAPE, which should promote additional development
later today. Farther west, latest CAMs/HREF suggest scattered
convection will backbuild along the front but will be delayed
toward the late afternoon and evening hours. There's still some
potential for a few strong storms given moderate to strong
instability and modest deep shear. The forecast has been adjusted
to update timing of PoPs.

In addition, heat stress remains a concern. Dewpoints are in the
mid 70s across most of the area, and with temps set to rise into
the mid to upper 90s across the western half, heat indices should
reach advisory criteria. There also remain concerns of greater
impacts, particularly in Franklin and Lincoln counties, because
this is ongoing while there are still several power outages. /DL/

Prior discussion below:

Today through Tuesday night...

Today will feel a little more like summer but change will be on the
way. As Ida continues to affect portions of the Ohio Valley and into
the Mid Atlantic today, caught up in an upper trough. To our west, a
589dm upper ridge across Texas will begin to shift east and affect
portions of our region. This puts the forecast area under northwest
flow aloft. As Ida continues to pull away, it will help drop a cold
front south into the Lower Mississippi River Valley region. Ahead of
this front, compressional heating will occur, and combined with the
increasing heights from the west, temperatures will be quite warm
today. Highs look to reach the upper 90s in the west and even up to
the mid 90s in the I-55 corridor. GEFS percentiles indicate that 850
mb temperatures today will be in the 90th to 97th percentile from
north Louisiana into the I-55 corridor. With moisture pooling ahead
of this cold front, indications are that we could dewpoints rise
significantly today and even see an unwelcome return to the lower
80s dewpoints ahead of this front. Because of this increase in
moisture and hot temperatures, heat indices will be quite the
concern today. There was already concern for heat stress in
locations where power outages continue but it is looking like heat
indices topping 105 and nearing 110 degrees will be possible across
a much larger area. Because of this, have gone ahead with a Heat
Advisory for locations roughly along and west of the I-55 corridor.

As this front interacts with daytime heating and increased
moisture(PW values forecast to be around 1.7 inches), convection
should develop by mid-day and continue through the evening. It is
even possible some convection could linger a bit later into the
night, as indicated by some of the hi-res model guidance. While
there is nothing currently outlooked, there may be some concern for
strong to at least isolated severe storms today. MUCAPE will be
around 2500-3000 J/kg(or higher depending on which model you look
at) with 25-28C Vertical Totals. There do appear to be rather poor
mid-level lapse rates and deep layer shear is on the magnitude of 15-
20kts. Will need to assess the microburst potential with this
mornings sounding. Gusty winds, lightning and locally heavy
downpours would be the main concern. Given recent rainfall this
could lead to some localized flooding but convection should be
progressive enough to preclude this mention at this time. /28/

Thursday through Tuesday...

Thursday will be the first day to see significantly cooler and drier
weather this week as a cold front moves south through the area. Deep
layer northerly flow behind the trough enhanced by the remnant
circulation of Ida will help the front make seasonably deep
progress, perhaps as far south as just beyond the northern Gulf
coast. While day time temperatures will be a bit cooler, the frontal
airmass changes will be most noticeable at night, when temperatures
Thursday night will dip into the 60s F for most. A seasonably warm
day Friday will be followed by another night of efficient cooling in
the post frontal airmass with similar temperatures for lows. The air
will be noticeably less humid than earlier this week with a near
zero rain chance after the front Thursday evening, Friday, and into
Saturday morning.

Cool snaps are rarely long lived in the ArkLaMiss in early September
and daily heating combined with frontolysis near the coast will lead
to modification of the postfrontal airmass by weekend. With this,
upper heights will also be on the rise and the boundary layer flow
will become generally more southerly as the surface high center
moves east of our area and return flow from the Gulf becomes
dominant. Subsequently, daily highs will begin to be more seasonal
through the weekend, in the lower to middle 90s F, and humidity will
begin to creep up with dewpoints in the upper 60s F and lower 70s F.
Rain and isolated thunderstorm chances will also be on the rise
with the increases in diurnal instability and increasing boundary
layer moisture (Td AOA 70F, PWs >1.75")

Due to extensive infrastructure impacts to the power grid from
Hurricane Ida, additional sensitivity continues to be warranted for
the interests of our neighbors in our southern Mississippi counties
in regards to heat indices. While the current long range forecast
suggests heat indices will generally remain below 105 F, should heat
indices over 100 F look likely, formal warning and/or forecast
products may be required should utility interruptions remain
widespread. This situation will continue to be closely monitored.
/86/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       95  72  89  67 /  30  36   8   2
Meridian      92  69  87  64 /  41  37   3   2
Vicksburg     98  74  92  69 /  23  30  10   3
Hattiesburg   92  73  90  69 /  33  42  22   3
Natchez       95  72  91  70 /  22  27  31   5
Greenville    96  70  89  65 /  23  11   2   1
Greenwood     94  69  89  64 /  28   8   1   1

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 7 PM CDT this evening for MSZ018-019-025-027-
     034>036-040>043-047>049-053>055-059>064-072.

LA...Heat Advisory until 7 PM CDT this evening for LAZ007>009-015-016-
     023>026.

AR...Heat Advisory until 7 PM CDT this evening for ARZ074-075.

&&

DL/28/86
Hazardous weather outlook, Sep 1, 4:15 AM CDT, 8 hours 48 minutes before
Hazardous Weather Outlook
National Weather Service Jackson MS
415 AM CDT Wed Sep 1 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025-034>036-
040>043-047>049-053>055-059>064-072-020915-
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Washington-Humphreys-Holmes-Issaquena-Sharkey-
Yazoo-Madison MS-Warren-Hinds-Rankin-Claiborne-Copiah-Simpson-
Jefferson-Adams-Franklin MS-Lincoln-Lawrence-Jefferson Davis-
Marion-
415 AM CDT Wed Sep 1 2021

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

.DAY ONE...Today and Tonight

DANGEROUS HEAT
THREAT...Elevated
TIMING...Today

Temperatures in the mid to upper 90s will combine with ample
moisture to bring heat indices of around 105 to 110 degrees today.
Residents should exercise caution when spending prolonged periods
outdoors. Take breaks, stay hydrated and find cool locations when
possible.

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

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

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 Tuesday.

MSZ030>033-038-039-045-046-051-052-057-058-020915-
Clay-Lowndes-Choctaw-Oktibbeha-Winston-Noxubee-Neshoba-Kemper-
Newton-Lauderdale-Jasper-Clarke-
415 AM CDT Wed Sep 1 2021

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

.DAY ONE...Today and Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

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 Tuesday.

MSZ026>029-037-044-050-056-065-066-073-074-020915-
Grenada-Carroll-Montgomery-Webster-Attala-Leake-Scott-Smith-
Covington-Jones-Lamar-Forrest-
415 AM CDT Wed Sep 1 2021

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

.DAY ONE...Today and Tonight

DANGEROUS HEAT
THREAT...Limited
TIMING...Today

Temperatures in the low to mid 90s will combine with ample
moisture to bring heat indices around 100 to 105 degrees. Use
caution when outdoors for prolonged periods of time.

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

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

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 Tuesday.

28

&&

...HAZARD LEGEND...

*DANGEROUS HEAT*
Extreme...Extreme heat is expected with peak heat index values
 in excess of 110 degrees for multiple days. Heat stroke continues
 to be a major concern.
Significant...Dangerous heat expected with peak heat index values
 in excess of 110 degrees. Heat stroke will be a significant
 concern.
Elevated...Dangerous heat likely with peak heat index values
 ranging from 106 to 110 degrees. Heat exhaustion will be likely.
Limited...Caution is advised for possible dangerous heat as
 heat index values peak near 105 degrees. Heat exhaustion will
 be possible.

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

NWS JAN Home page...
   https://www.weather.gov/jan
Stay Aware, Stay Safe NWS JAN Briefing Page...
   https://www.weather.gov/jan/safe
Latest Weather Briefing...
   https://www.weather.gov/jan/weather_briefing

Tropical page...
   https://www.weather.gov/srh/tropical?office=jan
National Hurricane Center Home Page...
   https://www.nhc.noaa.gov/
Find NWS JAN on Facebook...
   https://www.facebook.com/NWSJacksonMS
Follow NWS JAN on Twitter...
   @NWSJacksonMS
Follow NWS JAN on Youtube...
   https://www.youtube.com/user/NWSJacksonMiss

In the hours before

Local storm report, Sep 1, 11:18 AM CDT, 1 hour 45 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
1118 AM CDT WED SEP 1 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0300 PM     NON-TSTM WND DMG MERIGOLD                33.84N 90.73W
08/30/2021                   BOLIVAR            MS   BROADCAST MEDIA

            A TREE WAS DOWNED ACROSS A STREET IN
            MERIGOLD.

&&

DL
Special weather statement, Sep 1, 1:03 PM CDT, 0 minutes before
Special Weather Statement
National Weather Service Jackson MS
103 PM CDT Wed Sep 1 2021

MSZ031-011845-
Lowndes MS-
103 PM CDT Wed Sep 1 2021

...A strong thunderstorm will impact portions of northeastern Lowndes
County through 145 PM CDT...

At 102 PM CDT, Doppler radar was tracking a strong thunderstorm near
Caledonia, or 9 miles north of Columbus AFB, moving southeast at 35
mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated. A 54 MPH wind gust was measured at the
         Aberdeen Airport.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Columbus, Columbus AFB, Caledonia, Kolola Springs and Steens.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3340 8829 3366 8847 3367 8845 3367 8844
      3368 8843 3367 8842 3369 8839 3369 8837
      3372 8833 3374 8833 3374 8825
TIME...MOT...LOC 1802Z 328DEG 29KT 3376 8840

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

DL

The office that day

Everything else NWS Jackson, MS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 1, 4:08 AM CDTHeat AdvisoryJANAdams, Bolivar, Carroll, Claiborne, Copiah, Franklin and 18 more15 hr
Sep 1, 1:10 PM CDTSevere Thunderstorm WarningJANLowndes38 min
Sep 1, 2:37 PM CDTSpecial Weather StatementJANNoxubee23 min
Sep 1, 2:46 PM CDTSpecial Weather StatementJANClay29 min
Sep 1, 3:13 PM CDTSpecial Weather StatementJANChoctaw32 min
Sep 1, 3:25 PM CDTSevere Thunderstorm WarningJANClay, Lowndes, Noxubee, Oktibbeha50 min
Sep 1, 3:30 PM CDTSevere Thunderstorm WarningJANAttala, Choctaw, Winston45 min
Sep 1, 3:34 PM CDTSpecial Weather StatementJANCarroll41 min
Sep 1, 4:02 PM CDTSpecial Weather StatementJANCarroll, Holmes43 min
Sep 1, 4:20 PM CDTSevere Thunderstorm WarningJANKemper, Noxubee40 min
Sep 1, 4:35 PM CDTSevere Thunderstorm WarningJANAttala, Carroll, Holmes, Leake, Madison, Yazoo40 min
Sep 1, 4:42 PM CDTSevere Thunderstorm WarningJANAttala, Kemper, Lauderdale, Leake, Neshoba, Newton and 1 more48 min
Sep 1, 5:00 PM CDTSevere Thunderstorm WarningJANKemper45 min
Sep 1, 5:04 PM CDTSevere Thunderstorm WarningJANHolmes, Humphreys, Yazoo41 min
Sep 1, 5:07 PM CDTSevere Thunderstorm WarningJANLeake, Madison, Rankin, Scott, Yazoo68 min
Sep 1, 5:19 PM CDTSevere Thunderstorm WarningJANClarke, Jasper, Lauderdale, Newton56 min
Sep 1, 5:34 PM CDTSevere Thunderstorm WarningJANKemper, Lauderdale, Leake, Neshoba, Newton34 min
Sep 1, 5:45 PM CDTSevere Thunderstorm WarningJANMadison, Yazoo60 min
Sep 1, 6:05 PM CDTSpecial Weather StatementJANClarke, Jasper, Rankin, Scott, Simpson, Smith55 min
Sep 1, 6:14 PM CDTSevere Thunderstorm WarningJANHinds, Madison, Rankin, Simpson76 min
Sep 1, 6:15 PM CDTSevere Thunderstorm WarningJANClarke, Jasper, Lauderdale, Newton60 min
Sep 1, 6:37 PM CDTSevere Thunderstorm WarningJANClarke, Jasper, Simpson, Smith53 min
Sep 1, 5:01 PM CDTSpecial Weather StatementJANAshley44 min

Nearby

Special Weather Statements in Mississippi, 2021Every special weather statement in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.