Alert archive / Minnesota / Special Weather Statements in 2021

Special Weather Statement, NWS Twin Cities, MN

August 27, 2021Ramsey County, Minnesota

NWS Twin Cities, MN issued this special weather statement at Aug 27, 2021, 6:12 AM CDT for Ramsey County, Minnesota. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 27, 2021, 6:12 AM CDT (11:12 UTC)
Expired
Aug 27, 2021, 8:15 AM CDT
In force
2 hr
Issued by
NWS Twin Cities, MN

County Ramsey County, MN

The radar

The Minneapolis radar (KMPX), 31 km from the middle of the area, began a volume at 11:15 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

Minneapolis, MN (KMPX), launched 00:00Z, 11.2 hours before the alert went out and 33 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, Minneapolis, MN at 00:00Z on 2021-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2021-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 393 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
792 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
393 m²/s²
0-3 km storm-relative helicity
392 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

678 
WWUS83 KMPX 271112
SPSMPX

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Twin Cities/Chanhassen MN
612 AM CDT Fri Aug 27 2021
 
MNC003-037-053-123-163-271315-
Hennepin-Dakota-Anoka-Washington-Ramsey-
612 AM CDT Fri Aug 27 2021

...URBAN FLOODING EXPECTED...

Heavy rain with embedded thunder will cause minor flooding in the 
following counties...

Hennepin...Dakota...Anoka...Washington...Ramsey...

* Until 815 AM CDT.

* At 610 AM CDT, Doppler radar indicated heavy rain due to showers 
  and isolated thunderstorms. This will cause urban flooding in the 
  area. Up to one inch of rain has fallen in the past 30 to 60 
  minutes.

* Some locations that could experience minor flooding include...
  Minneapolis, St. Paul, Bloomington, Brooklyn Park, Plymouth, Eagan,
  Woodbury, Eden Prairie, Burnsville, Blaine, Minnetonka and Apple
  Valley.

Additional rainfall of up to an inch is expected in the next hour 
over the area. This additional rain will result in minor flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Runoff from heavy rainfall could cause flooding of small creeks and 
streams, urban areas, highways, streets and underpasses as well as 
other drainage areas and low lying spots.

&&

LAT...LON 4502 9308 4495 9300 4499 9291 4493 9284
      4489 9286 4477 9309 4476 9327 4481 9343
      4481 9352 4490 9353 4494 9331 4501 9341
      4506 9341 4510 9337 4510 9329 4514 9323
      4515 9312

$$

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 27, 12:56 AM CDTSpecial Weather StatementMPXMartin34 min
Aug 27, 2:06 AM CDTFlash Flood WarningMPXFreeborn5 hr
Aug 27, 2:59 AM CDTSpecial Weather StatementMPXBrown, Faribault, Martin, Redwood, Watonwan3 hr
Aug 27, 4:09 AM CDTFlash Flood WarningMPXFaribault, Freeborn3 hr

Nearby

Special Weather Statements in Minnesota, 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.