Alert archive / Nebraska / Heat Advisories in 2017

Heat Advisory 4, NWS North Platte, NE

July 19, 20177 counties in Nebraska

NWS North Platte, NE issued this heat advisory at Jul 19, 2017, 2:12 PM MDT for 7 counties in Nebraska. It took effect at Jul 20, 2017, 12:00 PM MDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Jul 19, 2017, 2:12 PM MDT (20:12 UTC)
In effect from
Jul 20, 2017, 12:00 PM MDT
Expired
Jul 20, 2017, 7:00 PM MDT
In force
7 hr
Issued by
NWS North Platte, NE

Counties Chase County, NE, Custer County, NE, Frontier County, NE, Garfield County, NE, Hayes County, NE, Holt County, NE, Wheeler County, NE

The radar

The North Platte radar (KLNX), 91 km from the middle of the area, began a volume at 20:16 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 8.2 hours before the alert went out and 64 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, N. Platte/Lee Bi, NE at 12:00Z on 2017-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 911 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2017-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.193958Sfc1 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
911 J/kg
Mixed-layer CIN
-333 J/kg
Mixed-layer LCL
1664 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
55 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

What forecasters said that day

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

NWS North Platte, NE wrote its last area forecast discussion before this heat advisory went out at Jul 19, 2:11 PM MDT, 1 minute earlier.

Area forecast discussion, Jul 19, 2:11 PM MDT, 1 minute before
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Hazardous weather outlook, Jul 19, 2:12 PM MDT, 0 minutes before
Hazardous Weather Outlook...UPDATED
National Weather Service North Platte NE
312 PM CDT Wed Jul 19 2017

NEZ004>010-022>029-035>038-056>059-069>071-094-202015-
Sheridan-Eastern Cherry-Keya Paha-Boyd-Brown-Rock-Holt-Garden-
Grant-Hooker-Thomas-Blaine-Loup-Garfield-Wheeler-Arthur-McPherson-
Logan-Custer-Deuel-Keith-Perkins-Lincoln-Chase-Hayes-Frontier-
Western Cherry-
312 PM CDT Wed Jul 19 2017 /212 PM MDT Wed Jul 19 2017/

This Hazardous Weather Outlook is for portions of western and
north central Nebraska.

.DAY ONE...TONIGHT.

Heat index values will exceed 100 degrees across much of western
and north central Nebraska during the early evening.

Isolated strong to briefly severe thunderstorms are possible this
evening, mainly along and north of a line from Oshkosh to Tryon
to Burwell. The best chances exist this evening into the small
hours. Large hail and damaging winds are the main hazards.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

Heat index values are likely to reach or exceed 100 degrees
Thursday and Friday across parts of southwest and north central
Nebraska. Additional heat advisories are in place Thursday for
parts of southwest and south central Nebraska.

Scattered short-lived severe thunderstorms are possible along and
north of a line from Oshkosh to Elsmere to O'Neill. Elsewhere,
isolated strong to briefly severe thunderstorms are possible.
Current thinking is the best window for thunderstorms will be
Thursday evening and night. Damaging winds and hail are the main
hazards, locally heavy rainfall will be possible as well.

While thunderstorms are forecast Friday and beyond with the best
chances occurring mainly in the afternoon and evening, the risk
of severe thunderstorms is low at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

&&

Get your weather, hydrological, and climate information at
http://www.weather.gov/northplatte

The office that day

Everything else NWS North Platte, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 18, 6:01 PM MDTSevere Thunderstorm WarningLBFChase, Perkins59 min
Jul 18, 6:04 PM MDTSpecial Weather StatementLBFHayes41 min
Jul 18, 6:26 PM MDTSevere Thunderstorm WarningLBFDeuel, Keith, Perkins23 min
Jul 18, 7:01 PM MDTSevere Thunderstorm WarningLBFChase44 min
Jul 18, 7:42 PM MDTSpecial Weather StatementLBFChase48 min
Jul 18, 7:47 PM MDTSevere Thunderstorm WarningLBFChase, Perkins16 min
Jul 19, 4:00 PM MDTSevere Thunderstorm WarningLBFBoyd, Holt45 min
Jul 19, 4:52 PM MDTSevere Thunderstorm WarningLBFHolt38 min
Jul 19, 5:30 PM MDTSevere Thunderstorm WarningLBFHolt60 min

Nearby

Heat Advisories in Nebraska, 2017Every heat advisory in 2017

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.