Temperatures reached the middle to upper 90s with dew points in the lower to middle 70s. This produced Heat Index values of around 105 degrees for a few hours on the afternoon of the 12th.
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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 HUN wrote it up.
Temperatures reached the middle to upper 90s with dew points in the lower to middle 70s. This produced Heat Index values of around 105 degrees for a few hours on the afternoon of the 12th.
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 Huntsville, AL wrote its last area forecast discussion before the first event at Jul 12, 11:02 AM CST, 58 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Huntsville AL 1202 PM CDT Thu Jul 12 2018 .UPDATE... For 18Z TAFS. && .NEAR TERM...(Today) Issued at 847 AM CDT Thu Jul 12 2018 Quiet morning across the Tennessee Valley as river valley fog has completely dissipated, resulting in prevailing clear conditions for now. To the northwest, the center of a strengthening upper-ridge will continue to build southeast into Middle Tennessee and Northern Alabama. This is evident on 12z soundings at OHX and BMX (along with forecasts of NAM/HRRR profiles later this afternoon) of showing a quite a bit of dry air aloft, evidence of some subsidence taking place. Still, plenty of moisture in the low-levels will allow for isolated to widely scattered shower and thunderstorm activity. The trigger will likely be a weak front dropping southwest from far eastern Tennessee into Georgia and eastern Alabama. Have oriented PoPs with the highest values south and east of the Tennessee River over Marshall and DeKalb Counties during the afternoon, and just an isolated mention over the Shoals. There should be plenty of CAPE to work with, and with an inverted-V sounding profile can't rule out an isolated strong storm capable of gusty winds. Otherwise, another hot day is expected and have nudged up temperatures ever so slightly. Highs will generally be in the lower 90s, with a few mid 90s across the MSL/HSV/DCU metros. This will create Heat Index values in the 100 to 105 degree range once again this afternoon -- with dewpoints in the low to mid 70s. .SHORT TERM...(Friday through Saturday night) Issued at 302 AM CDT Thu Jul 12 2018 Little change in the weather forecast is expected on Friday as the stalled front lingers underneath the eastern flank of a prevailing mid to upper level ridge. Similar environment will setup for Friday afternoon and evening especially instability and the lingering frontal boundary. As a result, have retained the potential for scattered storms throughout the afternoon/evening as daytime highs rise into the low 90s. However, with debris cloud cover from storms, could see somewhat lower daytime highs on both Friday and Saturday. Additionally, more mesoscale outflow boundaries that are more difficult to predict due to uncertainty with coverage of storms may be an additional cause for storms through the afternoon and possibly into the overnight both Friday night and Saturday night. A dampening ridge aloft will also contribute to higher potential for storms. As mentioned with Thursday's POPs, there could be a gradient in storm coverage from north to south. However, the front may briefly move north on Friday before completely dissipating leaving the mesoscale outflow boundaries as the singular lifting mechanism. Given the similar environment on Friday and Saturday there is still a threat for gusty winds up to 55 MPH with any storms that develop. In addition, with the weak front, most of the activity will be diurnally driven. So, will keep low POPs for the evening/overnight. .LONG TERM...(Sunday through Wednesday) Issued at 302 AM CDT Thu Jul 12 2018 After some better model agreement yesterday, the 12Z ECMWF is now more insistent on a stronger and more persistent upper ridge holding across the southern/southeast CONUS from Sunday into next week. Thus, there is considerable uncertainty with regard to thunderstorm coverage, especially with shortwaves on Sunday and Tuesday. The ECMWF depiction of the Tuesday shortwave and cold front is considerably weaker than the GFS. These differences are also reflected in the temperatures forecasts as well. The ECMX (MOS) max temperatures are several degrees warmer into the 90s vs the upper 80s to around 90 than that of the GFSX (MOS). All of this being said, the suggested blended forecast is still forecasting daily chances of thunderstorms, mainly diurnally enhanced by daytime heating, followed by quick dissipation during the early evening hours. The Tuesday arrival of the cold front and wave on the GFS (vs. ECMWF) would bring widespread coverage of thunderstorms. Will stick with the blends and closer to the ECMWF with chance PoPs until developments become more certain in due time. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) Issued at 1202 PM CDT Thu Jul 12 2018 VFR conditions will be the predominant flight category at each terminal through the period. SCT/BKN decks of CU/TCU will continue develop this afternoon. Can't rule out a VCTS/-TSRA at either site from mid/late afternoon. However, given their widely scattered nature, have left a mention out of the TAF at this time. The sky will clear after sunset once heating ends, with light and variable winds. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && NEAR TERM...AMP.24 SHORT TERM...SL.77 LONG TERM...17 AVIATION...AMP.24 For more information please visit our website at weather.gov/huntsville.
Hazardous Weather Outlook National Weather Service Huntsville AL 810 AM CDT Thu Jul 12 2018 ALZ001>010-016-TNZ076-096-097-131100- Lauderdale-Colbert-Franklin AL-Lawrence-Limestone-Madison-Morgan- Marshall-Jackson-DeKalb-Cullman-Moore-Lincoln-Franklin TN- 810 AM CDT Thu Jul 12 2018 This Hazardous Weather Outlook is for north Alabama and portions of southern middle Tennessee. .DAY ONE...Today and Tonight... Scattered thunderstorms will develop by midday as a weak cold front drop south into the region. A few strong thunderstorms capable of wind gusts up to 55 mph are possible. The thunderstorm activity will diminish rapidly after sunset. .DAYS TWO THROUGH SEVEN...Friday through Wednesday... Isolated to scattered thunderstorms are expected each day for most of the area, mainly during the afternoon and early evening hours. Some thunderstorms may be capable of producing gusty winds. .SPOTTER CALL TO ACTION STATEMENT... Activation of storm spotters and emergency management personnel is not anticipated at this time.
The national radar mosaic for the moment the first event began.
6 heat. Local standard time, as filed.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
The heat index reached 105 to 106 degrees during the afternoon of the 12th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alabama in 2018Every state in 2018This day in weather historyWarnings in Alabama, July 2018
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: 756708, 756709, 756710, 756712, 756713, 756714.