Alert archive / Missouri / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 258, NWS Springfield, MO

September 27, 2020Ozark County, Taney County, Missouri

NWS Springfield, MO issued this severe thunderstorm warning at Sep 27, 2020, 6:30 PM CDT for Ozark County, Taney County, Missouri. It was in force for 30 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 27, 2020, 6:30 PM CDT (23:30 UTC)
Expired: Sep 27, 2020, 7:00 PM CDT
In force: 30 min
Issued by: NWS Springfield, MO
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Ozark County, MO, Taney County, MO

The radar

The Springfield radar (KSGF), 87 km from the middle of the area, began a volume at 23:29 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

Springfield, MO (KSGF), launched 12:00Z, 11.5 hours before the alert went out and 98 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1285 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 139 m²/s²
0-3 km storm-relative helicity: 178 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Springfield, MO wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 27, 2:19 PM CDT, 4 hours 11 minutes earlier.

Area forecast discussion, Sep 27, 2:19 PM CDT, 4 hours 11 minutes before

Area Forecast Discussion
National Weather Service Springfield MO
219 PM CDT Sun Sep 27 2020

.SHORT TERM...(This evening through Tonight)

A cold front was entering the Ozarks this afternoon from the
northwest, forcing an area of deep convection along this feature.
Showers and thunderstorms will eventually become widespread in
nature, and impact nearly all locations across the region. A few
of the most intense storms will be capable of producing damaging
wind gusts up to 60 mph and large hail.

Instability continues to tick up this afternoon as a belt of 2000
j/kg mixed layer cape evolves across southwest Missouri by 22Z.
With deep layer shear ranging from 30 to 40 knots, this
combination will be capable of organizing a few storms. Some of
the latest high resolution models actually have some low level
cape evolving, however, very little low level helicity will be in
play.

We will be launching a 20z RAOB to provide the evening shift and
users with a snapshot of our environment, and take another look at
the low level cape/shear combination.

For tonight, showers and thunderstorms will continue behind the
front, eventually exiting south central Missouri by Monday
morning. Much colder air will spread in behind the front, causing
temperatures to fall into the 40s across most locations tonight.

Look for rainfall amounts to range from 0.30 to 1.00 inch by early
Monday morning. No flash flooding is expected at this time due to
the progressive nature of the storms and the very dry antecedent
conditions.

.LONG TERM...(Monday through Sunday)

Autumn air will spread in from the northwest, causing some of the
coldest temperatures we've observed since April. For Monday, highs
will struggle to warm out of the mid 60s.

In addition to the colder weather, will come an extended period
of dry conditions with no precipitation chances going from Monday
through next weekend. This dry spell will be accompanied by a
continental airmass with Canadian origin. Deep northwest flow will
persist through the upcoming weekend, forcing another cold front
to approach by Thursday. This will cool temperatures by a few
degrees for Thursday into Friday.

No freezing temperatures are expected this week, however we could
see some reading into the upper 30s Thursday and Friday nights,
especially in the eastern Ozarks.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)

Pilots flying in and out of southwest Missouri can expect stormy
weather late this afternoon and through the evening hours. Pilots
will need to monitor radar trends as severe weather will be
possible in some of the more intense storms.

Showers and thunderstorms will likely linger into the late
evening, and overnight period over some locations. Flight
conditions will be lowered as storms directly impact airfields.

A cold front approaching from the northwest is the main forcing
mechanism with these storms, which will also cause surface winds
to shift to the northwest later tonight and through tomorrow.

Safe Travels.

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...Cramer

Hazardous weather outlook, Sep 27, 6:09 PM CDT, 21 minutes before

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In the hours before

Local storm report, Sep 27, 5:01 PM CDT, 1 hour 29 minutes before

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Local storm report, Sep 27, 5:14 PM CDT, 1 hour 16 minutes before

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The office that day

Everything else NWS Springfield, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 27, 2:03 PM CDT	Severe Thunderstorm Warning	SGF	Morgan	23 min
Sep 27, 3:41 PM CDT	Severe Thunderstorm Warning	SGF	Dallas, Polk	49 min
Sep 27, 3:49 PM CDT	Severe Thunderstorm Warning	SGF	Camden, Dallas, Hickory, Laclede	56 min
Sep 27, 5:48 PM CDT	Severe Thunderstorm Warning	SGF	Christian, Douglas, Taney	42 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2020 Every severe thunderstorm warning in 2020

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.