Alert archive / Colorado / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 21, NWS Denver/Boulder, CO

May 27, 2013Logan County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 27, 2013, 5:32 PM MDT for Logan County, Colorado. It was in force for 28 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 27, 2013, 5:32 PM MDT (23:32 UTC)
Expired: May 27, 2013, 6:00 PM MDT
In force: 28 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Logan County, CO

The radar

The Denver radar (KFTG), 143 km from the middle of the area, began a volume at 23:32 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.

What was reported inside it

Time	Report	Where	Remark
May 27, 5:33 PM MDT	HAIL 1.5	Sterling, CO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 27, 1:19 PM MDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.5 hours before the alert went out and 74 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: 4442 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

760 
WUUS55 KBOU 272332
SVRBOU
COC075-280000-
/O.NEW.KBOU.SV.W.0021.130527T2332Z-130528T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
532 PM MDT MON MAY 27 2013

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN LOGAN COUNTY IN NORTHEAST COLORADO...

* UNTIL 600 PM MDT

* AT 531 PM MDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR STERLING...
  MOVING SOUTH AT 25 MPH.

  HAZARD...HALF DOLLAR SIZE HAIL AND 60 MPH WIND GUSTS. 

  SOURCE...RADAR INDICATED. AT 527 PM HALF DOLLAR SIZE HAIL WAS 
           REPORTED IN NORTHWEST STERLING.

  IMPACT...HAIL DAMAGE TO VEHICLES AND CROPS IS EXPECTED. EXPECT 
           WIND DAMAGE TO ROOFS...SIDING AND TREES. 

* LOCATIONS IMPACTED INCLUDE...
  STERLING AND ATWOOD. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM IS PRODUCING LARGE HAIL. SEEK SHELTER NOW INSIDE A STURDY
STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 4044 10304 4044 10332 4066 10330 4069 10316
TIME...MOT...LOC 2331Z 347DEG 22KT 4060 10322 

HAIL...1.25IN
WIND...60MPH

$$

GIMMESTAD

1 follow-up statement

933 
WWUS55 KBOU 272348
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
548 PM MDT MON MAY 27 2013

COC075-280000-
/O.CON.KBOU.SV.W.0021.000000T0000Z-130528T0000Z/
LOGAN CO-
548 PM MDT MON MAY 27 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM MDT
FOR SOUTHWESTERN LOGAN COUNTY...

AT 548 PM MDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR STERLING...
MOVING SOUTHEAST AT 25 MPH.

HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS. 

SOURCE...RADAR INDICATED. 

IMPACT...HAIL DAMAGE TO VEHICLES AND CROPS IS EXPECTED. EXPECT WIND 
         DAMAGE TO ROOFS...SIDING AND TREES. 

LOCATIONS IMPACTED INCLUDE...
SOUTHEASTERN STERLING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 4060 10311 4044 10304 4044 10319 4062 10317
      4062 10312
TIME...MOT...LOC 2348Z 333DEG 20KT 4058 10313 

HAIL...1.00IN
WIND...60MPH

$$

GIMMESTAD

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 27, 1:46 PM MDT	Severe Thunderstorm Warning	BOU	Washington	59 min
May 27, 3:51 PM MDT	Severe Thunderstorm Warning	BOU	Logan	39 min
May 27, 4:31 PM MDT	Tornado Warning	BOU	Logan	29 min
May 27, 5:03 PM MDT	Tornado Warning	BOU	Logan	27 min
May 27, 5:21 PM MDT	Special Weather Statement	BOU	Logan	39 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2013 Every severe thunderstorm warning in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.