Severe Thunderstorm Warning 59, NWS Denver/Boulder, CO

188 
WWUS55 KBOU 291834
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
1234 PM MDT TUE MAY 29 2018

COC075-291845-
/O.CON.KBOU.SV.W.0059.000000T0000Z-180529T1845Z/
Logan CO-
1234 PM MDT TUE MAY 29 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 PM MDT
FOR SOUTHEASTERN LOGAN COUNTY...

At 1233 PM MDT, a severe thunderstorm was located 7 miles northwest
of St Petersburg, or 14 miles east of Sterling, moving east at 10
mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

This severe thunderstorm will remain over mainly rural areas of
southeastern Logan County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4056 10300 4063 10300 4072 10286 4053 10283
TIME...MOT...LOC 1833Z 270DEG 9KT 4060 10295 

HAIL...1.00IN
WIND...<50MPH
 
$$

KRIEDERMAN

371 
WWUS55 KBOU 291841
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
1241 PM MDT TUE MAY 29 2018

COC075-291851-
/O.EXP.KBOU.SV.W.0059.000000T0000Z-180529T1845Z/
Logan CO-
1241 PM MDT TUE MAY 29 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN LOGAN COUNTY WILL
EXPIRE AT 1245 PM MDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

LAT...LON 4056 10300 4063 10300 4072 10286 4053 10283
TIME...MOT...LOC 1841Z 270DEG 9KT 4060 10292 

$$

KRIEDERMAN

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1045 AM MDT Tue May 29 2018

.UPDATE...
Issued at 1045 AM MDT Tue May 29 2018

Satellite pictures are showing the upper low circulation center
over southwestern South Dakota. There is a pretty decent batch of
moisture moving down the back side of it and into the northwestern
CWA at this time. There is some convective cloudiness developing
over the high terrain right now. There is week flow out on the
plains and not much of any convergence areas. Dew points are in
the mid 40s F for the western plains and mid 50s F for the eastern
plains. The forecast is on track. There is decent instability
still around with the cold air aloft but today there is weak
synoptic scale subsidence in place. There will be more heating
today than yesterday and there is still some CAPE progged for the
CWA this afternoon. The highest values are around 1000 J/kg over
the eastern border. Will make some cosmetic adjustments.

&&

.SHORT TERM...(Today and tonight)
Issued at 339 AM MDT Tue May 29 2018

Current satellite shows the upper level low in southeast Wyoming
early this morning, with an upper level jet max moving across
southern Colorado. There is still some lift on the left exit
region of this jet max, with a few showers and storms still
attempting to develop on the nose of this feature. As a result,
can't rule out a couple showers lingering past daybreak over the
far eastern/southeastern sections of the forecast area. There is
also some wrap around moisture sneaking back toward our northern
mountain areas, so will have some low PoPs there. Otherwise, the
forecast area will be dry this morning.

For this afternoon, we still expect isolated to scattered
thunderstorm development as the cold pool aloft remains over the
forecast area. There is some MLCAPE, but closer to 200-700 J/kg
in most areas. Still can't rule out a couple stronger storms over
the eastern plains where higher dewpoints will push values to
around 1000 J/kg, but only an isolated severe threat there.
Otherwise mostly small hail (thanks to the cold air aloft) and
brief moderate rain with the stronger storms today.

Skies will clear rather quickly this evening with rapid
stabilization after the loss of daytime heating.

.LONG TERM...(Wednesday through Monday)
Issued at 339 AM MDT Tue May 29 2018

On Wednesday, upper level high pressure is centered along the west
coast of the United States with an upper level ridge of high
pressure over the Rocky Mountain Region. Models are all showing some
afternoon and evening convection across north central and
northeastern Colorado. However, inverted V soundings would suggest
mainly light rain and gusty winds. However, one or two strong storms
may be possible further east on the plains where higher surface
dewpoints exist.

On Thursday, the upper trough deepens over the western United States
with a moderate and dry southwest flow aloft. This pattern should
result in above normal temperatures and dry weather across the
region

On Friday, the upper trough moves over the central and northern
Rockies with gusty westerly winds over the region. The warm and dry
weather combined with breezy conditions may result in elevated fire
danger across South Park and the southern foothills Friday
afternoon and evening.

A dry cold front associated with the upper trough moving north of
Colorado will bring cooler temperatures and continued dry weather to
northeastern Colorado on Saturday.

Sunday into Monday, moisture and instability may increase across the
plains due to east to southeasterly winds at the surface. This
moisture combined with a couple upper level disturbances may lead to
an increased chance for afternoon and evening thunderstorms mainly
east of Denver.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1045 AM MDT Tue May 29 2018

Winds will be light this afternoon with variable direction. My
mid/late afternoon there is some hint of northerly directions.
Normal drainage patterns can be expected tonight. There should
be no ceiling issues this afternoon or tonight. There will be a
10 to 20% chance of -TSRA at DIA this afternoon/early evening.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&

UPDATE.......RJK
SHORT TERM...Barjenbruch
LONG TERM....Kalina
AVIATION.....RJK

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1104 AM MDT Tue May 29 2018

COZ030>051-301715-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1104 AM MDT Tue May 29 2018

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...This Afternoon and Tonight

A few showers and thunderstorms will develop in the mountains this
morning and spread across the plains by early afternoon. A couple
stronger to possibly severe storms will be possible on the
eastern plains. The main threat from the storms would be hail up to
1 inch in diameter. Elsewhere, storms will produce mainly small
hail, brief moderate rain, wind gusts to 40 mph, and lightning.

Thunderstorms are expected to diminish quickly this evening as the
airmass stabilizes, with skies clearing before midnight.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Scattered afternoon and evening thunderstorms are expected on
Wednesday. Most of the storms will produce light rain and gusty
winds with a few stronger storms possible on the plains east of
Denver.

After Wednesday, a generally drier and warmer weather pattern
develops.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.