Scattered thunderstorms developed in an unstable air mass across Mississippi during the late morning of July 8th. An upper-level shortwave trough passing through the region brought increased flow and helped to organize these thunderstorms into a line of strong to severe storms by the afternoon.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS JAN wrote it up.
Scattered thunderstorms developed in an unstable air mass across Mississippi during the late morning of July 8th. An upper-level shortwave trough passing through the region brought increased flow and helped to organize these thunderstorms into a line of strong to severe storms by the afternoon. Damaging wind gusts and isolated flash flooding occurred in the Pine Belt region of Mississippi with this line of storms.
The local office's own words before the first event, 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 the first event at Jul 8, 10:17 AM CST, 3 hours 43 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1117 AM CDT Wed Jul 8 2020 .UPDATE... Updated for morning discussion. && .DISCUSSION... Showers and thunderstorms - primarily associated with a decaying MCS from early this morning - will continue to move across the forecast area through this afternoon. Some stabilization behind the MCS will limit further activity in its wake for a few hours, but westerly flow bringing in additional moisture and daytime heating could see additional showers or storms even in our northwestern zones during the afternoon. Lapse rates are fairly weak given the moist air mass in place across the region, so severe thunderstorms are not anticipated. Gusty winds with the strongest storms and locally heavy rainfall fed by the deeper moisture and instability will be the primary hazards today. After an initial burst of heavy rain training across far northeast LA early this morning, convection has been progressive across the rest of the area so far this morning. Will have to monitor for any other areas of training storms, as efficient rain production could boost flash flooding chances in those situations. /NF/ Prior discussion below: Today and Tonight: WV imagery this morning showing a more robust warm advection plume over the forecast area with a distinctive drop off in moisture to the west over south AR in proximity to the mid level shortwave. This forcing combined with the continued deep tropical moisture and limited heating will result in abundant convective development today. Already, convection has increased over the upper ArkLaMiss Delta region and will gradually expand later this morning as the wave moves east. Until this happens, locally heavy rainfall amounts may be seen over the upper Delta region as storms move repeatedly over the same areas. As the wave departs, ridging over the northwest Gulf of Mexico will bring about a more northwesterly flow regime tonight with the widespread tropical PWs finally beginning to dwindle./GG/ Thursday through Wednesday... A pattern change will be underway at the start of the forecast period tomorrow as a northwest flow regime becomes established across the Mississippi River Valley. This will occur as a stout ridge strengthens over the Desert Southwest and a mean downstream trough becomes entrenched and amplifies over the eastern CONUS with the trough axis extending down the spine of the Appalachian Mountains. A few showers and storms are likely to be ongoing tomorrow morning across northern portions of the area with additional development and increasing coverage expected through the morning and into the afternoon as the first of several perturbations embedded within the northwesterly flow drops into the area. Overnight hi-res CAM guidance differs on exact placement, but a northwest to southeast oriented band of showers and storms is expected roughly along and northeast of a line from Greenville to Jackson to Meridian. Cloud cover tomorrow will help keep temperatures in the upper 80s to low 90s across much of the area with the warmest temperatures over southwest portions of the area where highs could climb to around 93 degrees. Resulting heat index values will be near the 105 degree mark, but uncertainty regarding cloud cover and duration of higher values will preclude mention of heat stress in the HWO/graphics for now but a limited threat area may be warranted once trends become more clear. By Friday and into the weekend dangerous heat and the potential for vigorous MCS activity will become the primary focus of the forecast. As the Desert Southwest ridge strengthens, the eastern edge will gradually encroach on the region with rising heights and anomalously warm 850mb temperatures, the later of which will be in the 99th percentile for early to mid July. Resulting afternoon high temperatures will climb into the mid 90s, especially Saturday and Sunday. Convection could keep highs in check on Friday, especially over northeast portions of the area, but will still be in the low to mid 90s. A combination of wet conditions from nearly a week of widespread rainfall and deep low-level moisture extending to ~850mb will support stifling dew points in the upper 70s to near 80 even during peak heating. This combination of anomalous low-level moisture (925mb specific humidity values in the 95th percentile) and temperatures in the mid 90s will result in oppressive and dangerous heat index values of 106-110 degrees with higher values not out of the question depending on degree of heating and how much, if any, moistures mixes out. As such, have upgraded much of the area to an elevated threat for heat stress in the HWO/graphics. In addition to dangerous heat, there will also be potential for at least one, if not two, vigorous MCS(s) to impact portions of the area. The synoptic pattern featuring anomalously strong northwest flow and a stationary frontal boundary draped through the Middle Mississippi River Valley is synonymous with local MCS climatology. Both the GFS and ECMWF depict upstream MCS activity emanating out of the Central Plains and propagating towards the area during the Friday through Saturday evening timeframe as two shortwave troughs rotate around the southwest ridge. As is typical with summer MCSs, model guidance will continue to differ with timing and placement of these storm complexes as they will be dependent on upstream mesoscale boundaries and details that can't be resolved at both this timeframe and within the coarser resolution of global models. Regardless of placement and timing, the parameter space across the Lower Mississippi River Valley will be rather impressive with copious amounts of instability and downdraft CAPE combined with 30- 40kts of deep-layer vertical wind shear and steepening mid-level lapse rates of 7.5 C/km. Any MCS that is able to take advantage of this environment will be vigorous and as such will need to keep a close eye on the potential as the weekend nears. By early next work week, guidance is in fairly good agreement that the southwest ridge will flatten and expand across the southern CONUS. This will keep a continued threat for heat stress into next week as temperatures remain in the mid to potentially upper 90s. Furthermore, the expanding ridge will shunt any diurnally driven storms further east as well with PoPs gradually dropping off to slight chance and confined over far eastern Mississippi. /TW/ && .AVIATION... 12Z TAF discussion: Mostly MVFR conditions will continue through the morning as showers and thunderstorms increase from the west. While VFR ceilings will become dominant by afternoon and continue into the evening, periodic showers and thunderstorms will drop conditions to MVFR for brief periods. The convection will diminish after midnight as ceilings lower to MVFR./GG/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 85 73 91 74 / 88 46 59 17 Meridian 85 72 90 73 / 87 48 69 24 Vicksburg 86 76 92 77 / 91 34 30 7 Hattiesburg 87 73 93 74 / 82 32 32 12 Natchez 87 74 92 74 / 79 27 13 4 Greenville 86 74 91 76 / 92 46 63 17 Greenwood 86 74 91 75 / 91 53 71 22 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && TW/NF/GG
Hazardous Weather Outlook National Weather Service Jackson MS 440 AM CDT Wed Jul 8 2020 ARZ074-075-LAZ007>009-015-016-023-025-MSZ018-019-025>028-034>036- 040>043-047>049-053-090945- Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland- Madison LA-Franklin LA-Tensas-Bolivar-Sunflower-Leflore-Grenada- Carroll-Montgomery-Washington-Humphreys-Holmes-Issaquena-Sharkey- Yazoo-Madison MS-Warren-Hinds-Rankin-Claiborne- 440 AM CDT Wed Jul 8 2020 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...Today and Tonight FLOODING THREAT...Limited TIMING...Through this afternoon Localized flash flooding due to heavy rain is possible, particularly in low lying and urban areas. (https://www.weather.gov/images/jan/graphicast/1.png) .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Dangerous heat with maximum heat index values of 105 degrees or greater is possible Friday into next week. (https://www.weather.gov/images/jan/graphicast/2.png) .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. LAZ024-026-MSZ029>033-037>039-044>046-050>052-054>066-072>074- 090945- Catahoula-Concordia-Webster-Clay-Lowndes-Choctaw-Oktibbeha-Attala- Winston-Noxubee-Leake-Neshoba-Kemper-Scott-Newton-Lauderdale- Copiah-Simpson-Smith-Jasper-Clarke-Jefferson-Adams-Franklin MS- Lincoln-Lawrence-Jefferson Davis-Covington-Jones-Marion-Lamar- Forrest- 440 AM CDT Wed Jul 8 2020 This hazardous weather outlook is for portions of northeast Louisiana, central Mississippi, east central Mississippi, north central Mississippi, northeast Mississippi, and south central Mississippi. .DAY ONE...Today and Tonight The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Dangerous heat with maximum heat index values of 105 degrees or greater is possible Friday into next week. (https://www.weather.gov/images/jan/graphicast/2.png) .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. 26 && ...HAZARD LEGEND... *FLOODING* Extreme...Widespread and significant flooding is likely. Significant...Widespread flash flooding is likely and significant flooding is possible. Elevated...Areas of flash flooding likely. Limited...Localized flash flooding is 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 ...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
Special Weather Statement
National Weather Service Jackson MS
918 AM CDT Wed Jul 8 2020
MSZ040-042-047-081445-
Warren MS-Yazoo MS-Issaquena MS-
918 AM CDT Wed Jul 8 2020
...STRONG THUNDERSTORMS WILL AFFECT NORTHEASTERN WARREN...YAZOO AND
EAST CENTRAL ISSAQUENA COUNTIES UNTIL 945 AM CDT...
At 918 AM CDT, Meteorologists were tracking strong thunderstorms
along a line extending from near Yazoo City to near Tinsley to 8
miles west of Phoenix. Movement was east at 25 mph.
Winds in excess of 40 mph will be possible with these storms.
Strong thunderstorms will be near...
Yazoo City around 925 AM CDT.
Tinsley around 930 AM CDT.
Phoenix around 940 AM CDT.
Benton, Little Yazoo and Myrleville around 945 AM CDT.
Other locations impacted by these storms include Eden, Satartia and
Bentonia.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.
High winds can bring down trees and large limbs resulting in serious
injury or property damage. Exercise extreme caution when outdoors
during such strong winds...and be especially aware of older trees.
&&
LAT...LON 3267 9070 3267 9066 3270 9067 3274 9061
3292 9049 3293 9045 3301 9043 3297 9022
3292 9010 3274 9021 3266 9028 3258 9040
3259 9044 3256 9045 3252 9052 3250 9052
3250 9059 3248 9061 3245 9060 3258 9082
TIME...MOT...LOC 1418Z 288DEG 22KT 3293 9043 3273 9055 3261 9070
NFSpecial Weather Statement
National Weather Service Jackson MS
1201 PM CDT Wed Jul 8 2020
MSZ047>049-053-081745-
Warren MS-Hinds MS-Rankin MS-Claiborne MS-
1201 PM CDT Wed Jul 8 2020
...THUNDERSTORMS PRODUCING LOCALLY HEAVY RAINFALL ACROSS
RANKIN...SOUTHERN WARREN... NORTHEASTERN CLAIBORNE AND HINDS
COUNTIES...
At 1158 AM CDT, Meteorologists were tracking thunderstorms producing
locally heavy rainfall along a line extending from near Johns to
near Yokena. Movement was southeast at 10 mph.
Torrential rainfall is occurring with these storms, and may lead to
localized flooding.
Locations impacted include...
Jackson, Pearl, Vicksburg, Brandon, Byram, Richland, Star, Florence,
Raymond, Terry, Utica, Dry Grove, Rocky Springs, Cato, Le Tourneau,
Whites, Johns, Yokena, Piney Woods and Reganton.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive your vehicle through flooded roadways.
&&
LAT...LON 3225 9097 3233 9090 3230 8975 3205 8973
3205 9072 3207 9103
TIME...MOT...LOC 1658Z 308DEG 10KT 3216 8991 3214 9088
DLSpecial Weather Statement National Weather Service Jackson MS 1231 PM CDT Wed Jul 8 2020 MSZ045-046-081830- Kemper MS-Neshoba MS- 1231 PM CDT Wed Jul 8 2020 ...A STRONG THUNDERSTORM WILL AFFECT KEMPER AND EAST CENTRAL NESHOBA COUNTIES THROUGH 130 PM CDT... At 1231 PM CDT, Meteorologists were tracking a strong thunderstorm over eastern Neshoba County, moving east at 25 mph. Winds in excess of 40 mph will be possible with this storm. Locations impacted include... De Kalb, Liberty, Blackwater, Herbert Springs, Tamola, Damascus, Bluff Springs, Forestdale, Porterville and Prismatic. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. High winds can bring down trees and large limbs resulting in serious injury or property damage. Exercise extreme caution when outdoors during such strong winds...and be especially aware of older trees. && LAT...LON 3259 8893 3285 8901 3292 8852 3258 8844 TIME...MOT...LOC 1731Z 262DEG 23KT 3269 8887 DL
Special Weather Statement
National Weather Service Jackson MS
259 PM CDT Wed Jul 8 2020
MSZ072>074-082045-
Lamar MS-Marion MS-Forrest MS-
259 PM CDT Wed Jul 8 2020
...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN MARION...FORREST
AND LAMAR COUNTIES UNTIL 345 PM CDT...
At 259 PM CDT, Meteorologists were tracking a strong thunderstorm
near Columbia, moving east at 30 mph.
Dime size hail and wind gusts up to 50 mph will be possible with this
storm.
This strong thunderstorm will be near...
Hattiesburg and Pine Ridge around 330 PM CDT.
Purvis and Oak Grove around 335 PM CDT.
West Hattiesburg around 340 PM CDT.
Other locations impacted by this storm include Corinth.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.
High winds can bring down trees and large limbs resulting in serious
injury or property damage. Exercise extreme caution when outdoors
during such strong winds...and be especially aware of older trees.
&&
LAT...LON 3101 8935 3101 8942 3098 8943 3098 8944
3101 8950 3101 8984 3107 8984 3108 8992
3115 8994 3142 8963 3143 8914 3091 8914
3091 8934
TIME...MOT...LOC 1959Z 269DEG 27KT 3124 8974
JMThe national radar mosaic for the moment the first event began.
3 thunderstorm wind, 2 flash flood. Local standard time, as filed.
A power line was blown down near New Hope-Kokomo Road.
A tree was blown down on Pittman Road.
Water blocked a portion of South High School Road in Columbia.
A tree was blown down on Tatum Salt Dome Road.
Water blocked part of Pine Burr Road near MS Highway 13 South.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Mississippi in 2020Every state in 2020This day in weather historyWarnings in Mississippi, July 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 910319, 910322, 911471, 910326, 911468.