Alert archive / Missouri / Red Flag Warnings in 2021
Red Flag Warning 2, NWS St. Louis, MO
NWS St. Louis, MO issued this red flag warning at Mar 31, 2021, 4:31 AM CDT for 22 counties in Missouri; Calhoun County, Illinois. It took effect at Mar 31, 2021, 12:00 PM CDT. It was in force for 7 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Mar 31, 2021, 4:31 AM CDT (09:31 UTC)
- In effect from
- Mar 31, 2021, 12:00 PM CDT
- Expired
- Mar 31, 2021, 7:00 PM CDT
- In force
- 7 hr
- Issued by
- NWS St. Louis, MO
All 23 counties
Calhoun County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 80 km from the middle of the area, began a volume at 09:36 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
Lincoln, IL (KILX), launched 00:00Z, 9.5 hours before the alert went out and 278 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1672 m above ground
- 0-6 km bulk shear
- 75 kt
- 0-1 km storm-relative helicity
- 66 m²/s²
- 0-3 km storm-relative helicity
- 297 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
948 WWUS83 KLSX 310931 RFWLSX URGENT - FIRE WEATHER MESSAGE National Weather Service Saint Louis MO 431 AM CDT Wed Mar 31 2021 ILZ098-MOZ018-019-026-027-034>036-041-042-047>052-059>064-072- 010000- /O.NEW.KLSX.FW.W.0002.210331T1700Z-210401T0000Z/ Audrain MO-Boone MO-Calhoun IL-Callaway MO-Cole MO-Crawford MO- Franklin MO-Gasconade MO-Knox MO-Lewis MO-Lincoln MO-Marion MO- Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO- Saint Charles MO-Saint Louis City MO-Saint Louis MO-Shelby MO- Warren MO- 431 AM CDT Wed Mar 31 2021 ...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR NORTHEAST AND CENTRAL MISSOURI AND A SMALL PART OF SOUTHWEST ILLINOIS... The National Weather Service in Saint Louis has issued a Red Flag Warning for wind and low relative humidity, which is in effect from noon today to 7 PM CDT this evening. * AFFECTED AREA...In Illinois, Fire Weather Zone 098. In Missouri, Fire Weather Zones 018, 019, 026, 027, 034, 035, 036, 041, 042, 047, 048, 049, 050, 051, 052, 059, 060, 061, 062, 063, 064 and 072. * 20 FOOT WINDS...Northwest 15 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 20 percent. * 10 HOUR FUELS...Less than 9 percent. * IMPACTS...These conditions are conducive for the rapid spread and growth of uncontrolled wildfires. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity, and dry fuels can contribute to extreme fire behavior. && $$ GKS
The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 31, 2:44 PM CDT | Freeze Warning | LSX | Boone, Callaway, Cole, Crawford, Franklin, Gasconade and 15 more | 42 hr |
Nearby
Red Flag Warnings in Missouri, 2021Red Flag Warnings in Illinois, 2021Every red flag warning 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.