Special Weather Statement, NWS North Platte, NE

Area Forecast Discussion
National Weather Service North Platte NE
628 PM CDT Fri Aug 3 2018

.SHORT TERM...(This evening through Saturday)
Issued at 340 PM CDT Fri Aug 3 2018

An upper level disturbance, moving through WY this afternoon, should
fire off one or two areas of thunderstorms and possibly a QLCS
extending north and south across a good portion of ncntl Nebraska.
The SREF shows modest mid level frontogenesis ahead of the
disturbance and the models show precipitable water increasing to 1.5-
1.75 inches. Model soundings indicate most of this water will be
loaded into the 700-300mb layer; potentially producing strong to
severe wind gusts with weak winds aloft. Gusty winds and heavy
rainfall have been added to the forecast for a few hours this
afternoon and this evening.

The convective arrangement should exit ncntl Nebraska early Saturday
morning. A weaker upper air disturbance should form off the Laramie
Range 18z-21z Saturday afternoon. Isolated to scattered thunderstorm
development is expected across ern WY which should move east into
wrn Nebraska. It is believed the convection this afternoon and this
evening will produce a stable meso high which will limit storm
coverage to isolated or low-end scattered across wrn Nebraska. The
model consensus shows precipitable water falling to around 1 inch
and the CAMS models such as the HREF, NAM12 and NAMnest support the
forecast for low POPs.

.LONG TERM...(Saturday night through Friday)
Issued at 340 PM CDT Fri Aug 3 2018

Not sure about the forcing and stability Saturday evening. Winds
aloft at 500mb increase to 40-50kt which might be too strong for
storm development given the limited instability that could be in
place with the wake of tonight's storms. The NAM and GFS show a
disturbance moving into Nebraska Saturday which would provide
forcing. The Bulk Richardson number in the NAM is favorable for
storm development and there is a stationary front draped across
ncntl Nebraska in both the NAM and GFS models. The model consensus
suggests just an isolated/low-end scattered thunderstorm chances.
The better moisture appears to lie across eastern Nebraska as
suggested by the ECM.

The models show very good moisture return east of highway 83 Sunday
with precipitable water increasing to over 1.5 inches again. Winds
aloft at 500mb remain strong at 40-50kt and sufficient elevated
instability is shown by the NAM for thunderstorms. No significant
height falls are shown by the models but cold air aloft is producing
steep lapse rates become steep of over 7C/km. The models suggested a
chance POP associated with a cold front and a southward propagating
MCS.

No significant rain chances are expected Monday and beyond. Just
isolated chances. The upper level flow will transition to northwest
flow without moisture return. H850mb winds become south but remain
very weak. The GFS indicates the deeper moisture would remain
sequestered across the Midsouth as a result of a stationary front.

&&

.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 628 PM CDT Fri Aug 3 2018

Thunderstorms increasing in coverage across southwest Nebraska,
to include the KLBF TAF site at the beginning of the TAF period.
Gusty winds and heavy rain to reduce visibility at the terminal
until 02z, possibly lasting until 04z. Aside from a few showers
the next hour, KVTN is expected to remain outside of thunderstorms
this evening.

Mainly VFR conditions outside of convective activity however. A more
prominent wind shift to the northwest will occur in the north
central part of the state after the passage of the storms and
associated trough by Saturday morning.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&

SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Roberg

Hazardous Weather Outlook
National Weather Service North Platte NE
341 PM CDT Fri Aug 3 2018

NEZ004>010-022>029-035>038-056>059-069>071-094-042045-
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-
341 PM CDT Fri Aug 3 2018 /241 PM MDT Fri Aug 3 2018/

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

.DAY ONE...TONIGHT.

Thunderstorms capable of gusty winds are likely this evening,
generally along and east of a line from Ogallala to Mullen to
Valentine. A few severe storms may develop capable of wind damage,
large hail and very heavy rainfall. The area of concern for these
storms is generally east of a line from Big Springs to Hyannis
and Merriman.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

Isolated thunderstorms are possible across western and north
central Nebraska Saturday afternoon and Saturday night. There is
a marginal threat for severe storms across all of western and
north central Nebraska. Large hail and damaging winds are
possible.

Thunderstorms are possible Sunday and Sunday night across all of
western and north central Nebraska. There is a marginal risk for
severe storms with large hail and damaging winds being the main
severe threats.

Thunderstorms are possible, at times, Monday through Wednesday
night. At this time, the risk of severe weather is uncertain.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed between 3 and 9 pm today along
and east of a line from Big Springs to Hyannis and Merriman.

&&

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

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
701 PM CDT FRI AUG 3 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0700 PM     TSTM WND GST     5 SSE HERSHEY           41.09N 100.96W
08/03/2018  E60 MPH          LINCOLN            NE   CO-OP OBSERVER

            ALSO REPORTING 0.75 INCH HAIL.

&&

JURGENSEN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
703 PM CDT FRI AUG 3 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0654 PM     HAIL             8 WNW NORTH PLATTE      41.18N 100.91W
08/03/2018  E1.00 INCH       LINCOLN            NE   PUBLIC

&&

JURGENSEN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
728 PM CDT FRI AUG 3 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0646 PM     TSTM WND GST     8 WSW NORTH PLATTE      41.09N 100.91W
08/03/2018  E80.00 MPH       LINCOLN            NE   NWS EMPLOYEE

            OFF DUTY EMPLOYEE PASSING THROUGH REPORTS 2 CAMPERS AND 1
            SEMI BLOWN OVER IN AREA OF MM 169 AND 171 ON INTERSTATE
            80. TIME ESTIMATED FROM RADAR.

&&

JURGENSEN

Special Weather Statement
National Weather Service North Platte NE
733 PM CDT FRI AUG 3 2018

NEZ036-057-059-040115-
McPherson NE-Lincoln NE-Keith NE-
733 PM CDT FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN KEITH...NORTHWESTERN
LINCOLN AND SOUTHWESTERN MCPHERSON COUNTIES UNTIL 815 PM CDT/715 PM
MDT/...

At 733 PM CDT/633 PM MDT/, Doppler radar was tracking a strong
thunderstorm 12 miles north of Sarben, or 20 miles southwest of
Tryon, moving northeast at 25 mph.

Dime size hail and wind gusts up to 50 mph will be possible with this
storm.

This storm will remain over mainly rural areas of northeastern
Keith...northwestern Lincoln and southwestern McPherson Counties.

This includes Highway 92 near mile marker 189.

LAT...LON 4125 10119 4130 10132 4156 10125 4145 10089
TIME...MOT...LOC 0033Z 211DEG 22KT 4134 10122

Roberg

Special Weather Statement
National Weather Service North Platte NE
746 PM CDT FRI AUG 3 2018

NEZ008>010-040130-
Brown NE-Holt NE-Rock NE-
746 PM CDT FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR ROCK...SOUTHEASTERN BROWN AND
WEST CENTRAL HOLT COUNTIES UNTIL 830 PM CDT...

At 746 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Newport to 10 miles west of Rose. Movement
was east at 35 mph.

Half inch hail and wind gusts up to 50 mph will be possible with
these storms.

Locations impacted include...
Bassett, Stuart, Newport, Duff, Pony Lake, Sybrant, Twin Lakes State
Wildlife Management Area and Johnsons Corner.

This includes the following highways...
 Highway 183 between mile markers 156 and 182.
 Highway 20 between mile markers 257 and 283.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4270 9899 4219 9931 4218 9989 4269 9950
TIME...MOT...LOC 0046Z 251DEG 30KT 4255 9941 4220 9972

Roberg

Special Weather Statement
National Weather Service North Platte NE
827 PM CDT FRI AUG 3 2018

NEZ007-010-040215-
Holt NE-Boyd NE-
827 PM CDT FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN HOLT AND BOYD COUNTIES
UNTIL 915 PM CDT...

At 827 PM CDT, Doppler radar was tracking a strong thunderstorm 10
miles north of Stuart, or 23 miles northeast of Bassett, moving
northeast at 45 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations impacted include...
Spencer, Butte, Lynch, Naper, Gross, Bristow, Dustin, Anoka, Hull
Lake State Wildlife Management Area, Spencer Dam, Midway, Parshall
Bridge State Wildlife Management Area and Anncar.

This includes the following highways...
 Highway 281 between mile markers 197 and 223.
 Highway 12 between mile markers 83 and 133.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4293 9844 4293 9841 4288 9831 4286 9831
      4265 9857 4262 9917 4278 9924 4300 9923
      4300 9850
TIME...MOT...LOC 0127Z 218DEG 38KT 4276 9914

Taylor