Severe Thunderstorm Warning 63, NWS Des Moines, IA

844 
WWUS53 KDMX 282034
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
334 PM CDT MON MAY 28 2018

IAC099-282045-
/O.CON.KDMX.SV.W.0063.000000T0000Z-180528T2045Z/
Jasper IA-
334 PM CDT MON MAY 28 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 PM CDT
FOR NORTH CENTRAL JASPER COUNTY...

At 334 PM CDT, a severe thunderstorm was located near Baxter, or 8
miles north of Newton, moving west at 15 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of north
central Jasper County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4173 9297 4173 9314 4186 9310 4186 9306
      4184 9292
TIME...MOT...LOC 2034Z 107DEG 13KT 4181 9303 

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

Martin

524 
WWUS53 KDMX 282043
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
343 PM CDT MON MAY 28 2018

IAC099-282052-
/O.EXP.KDMX.SV.W.0063.000000T0000Z-180528T2045Z/
Jasper IA-
343 PM CDT MON MAY 28 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL JASPER COUNTY
WILL EXPIRE AT 345 PM CDT...
                
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 and heavy rain are still possible with this thunderstorm.

LAT...LON 4173 9297 4173 9314 4186 9310 4186 9306
      4184 9292
TIME...MOT...LOC 2042Z 099DEG 12KT 4181 9306 

$$

Martin

Area Forecast Discussion
National Weather Service Des Moines IA
1236 PM CDT Mon May 28 2018

...18z Aviation Update...

.SHORT TERM.../Today through Tonight/
Issued at 347 AM CDT Mon May 28 2018

Monday's weather will be a slight variation of Sunday's -- hot with
an isolated to scattered chance of afternoon thunderstorms mainly
focused near and west of I-35. Upper level ridge will remain over
the region, but will begin shifting eastward today as trough of low
pressure over the Intermountain West begins to lift northeastward.
850mb temperatures will be a degree or so lower than yesterday, but
will still be well above normal for this time of year. As was the
case yesterday, the available model guidance 10th percentile high
temperatures for both Des Moines and Waterloo would set new records
and the current forecast smashes those records again by 4 or more
degrees. Boundary layer mixing throughout the morning will have
dewpoints lowering into low and middle 60s in the afternoon. This
will translate to heat index values between the middle 90s to near
100 degrees. With the heat health system indicating an elevated
concern for urban effects of cumulative heat in this dry tropical
airmass and what will almost certainly be a third day in a row of a
record high temperature in Des Moines, a heat advisory will once
again be raised for the Des Moines metro this afternoon into early
this evening.

Beyond the heat today, a subtle shortwave trough embedded within the
longwave trough will eject toward the area impinging on western Iowa
by this afternoon. Convective allowing and to a lesser extent
convective permitting models all indicate showers and thunderstorms
beginning to develop by mid-afternoon. Unlike Sunday, the signal in
these models is much more robust as there will be synoptic scale
forcing versus the weak convergence/convective temperature
exceedance. However, there is still quite the disparity in placement
of the convection. Overall, models favor western Iowa as that is
where the weak forcing will be maximized, though time lagged HRRR,
WRF-ARW, and ESRL HRRR indicate the possibility of convection being
a bit farther east. For now, will focus shower and thunderstorm
chances over western parts of the forecast area this afternoon into
early this evening. RAP, NAM, and GFS soundings all indicate DCAPE
values near or well in excess of 1500 J/kg this afternoon so storms
may pose a risk of gusty winds.

After thunderstorms dissipate this evening, skies will be partly to
mostly clear. It will be another warm night, but low temperatures
should be several degrees away from record high low temperatures.

.LONG TERM.../Tuesday through Sunday/
Issued at 347 AM CDT Mon May 28 2018

Somewhat active to begin the extended range with two converging
systems nearing Iowa Tuesday into Wednesday. One being an upper
trough currently moving across the southern Rockies and the other
being Alberto moving through the Gulf of Mexico. The western US
trough will lift ENE through the western high plains of WY/CO/MT
Tuesday and into the Dakotas by early Wednesday, while Alberto lifts
north northwestward through FL and into IL/IN by early Wednesday.
Moisture will stream northward Tuesday into Wednesday and into Iowa
between these two systems. However the flow remains quite weak, so
overall push of moisture to be marginal. Expect mainly diurnally
driven storms initially Tuesday afternoon into early evening across
the area, with better chances for more widespread storms/rain
chances late Tuesday night into Wednesday morning as the two upper
troughs begin to somewhat merge and better push of moisture into the
state expected and the western upper trough nudges into
northern/western Iowa. As these two systems merge, they lift
northeastward into the Great Lakes region into Thursday. Therefore
expect precip chances shift more north and east into Wednesday
night, with dry conditions into Thursday.

Upper ridging then to build into the state Friday, with the GFS/EC
bringing another weak upper trough through the northern Plains
topping the ridge. EC stronger with the system than the GFS which
could bring another chance for some storms across the area Saturday
into Saturday night. Upper ridging then builds in stronger for
Sunday into early next week with dry conditions returning to end the
forecast period Sunday and beyond. Overall threat for severe storms
with any of the thunderstorm chances somewhat small. Instability
looking ok, but bulk deep layer shear fairly weak. Better chances as
you move to the western portion of the forecast area closer to the
upper trough Tuesday. As for temperatures overall pattern to suggest
the above average trend to continue through the entire forecast
period. Thermal ridge to build into Iowa Friday ahead of the weak
wave for Saturday which should allow temps to climb back into the
low to mid 90s. This may even be too cool, but did nudge guidance
temps up some for Friday into Saturday. Temperatures should then
cool a bit to closer to the seasonal averages behind Saturday's
system for Sunday into early next week.

&&

.AVIATION.../For the 18Z TAFS through 18Z Tuesday afternoon/
Issued at 1223 PM CDT Mon May 28 2018

VFR conditions will continue to prevail at most sites throughout
the TAF period. An unlucky few, namely KDSM/KFOD and possibly
KMCW, may see short periods of MVFR as isolated to scattered
convection is again expected today. However confidence is low in
storms actually affecting any of the sites and causing
restrictions due to the scattered nature expected. VCTS and any
restrictions will subside shortly after about 01z. Winds will
predominantly turn southerly into the afternoon, and complicating
matters is remnant outflow from morning convection/precipitation
over SW Wisconsin. It has moved through parts of NE and NC Iowa
and continues to produce easterly/southeasterly winds around 10-15
kts with gusts in excess of 20kts. Has and will continue to
affect KMCW/KALO over the next couple hours.

&&

.CLIMATE...
Issued at 347 AM CDT Mon May 28 2018

Forecast of Record Highs for Official Central Iowa Climate Sites

================================================
            |        Monday        |  Period
            |  Forecast   Record/  |    of
City        |    High      Year    |  Record
================================================
Des Moines        98      92/1895      1878-
Waterloo          97      93/2006      1895-
================================================

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for IAZ059-060.

&&

SHORT TERM...Ansorge
LONG TERM...Beerends
AVIATION...Curtis
CLIMATE...Ansorge

Hazardous Weather Outlook
National Weather Service Des Moines IA
218 PM CDT Mon May 28 2018

IAZ059-060-073-291100-
Dallas-Polk-Warren-
218 PM CDT Mon May 28 2018

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...This afternoon and tonight

A Heat Advisory is in effect for the area. Please refer to the
National Weather Service website at weather.gov/desmoines for
further details.

Isolated thunderstorms are expected late this afternoon and
evening. A strong storm or two is possible, producing small hail
and gusty winds.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Thunderstorm chances will return between Tuesday afternoon and
Wednesday evening, then again around Saturday. At this time the
threat of severe storms is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

IAZ004>007-015>017-023>028-033>039-044>050-057-058-061-062-
070>072-074-075-081>086-092>097-291100-
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun-
Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-
Boone-Story-Marshall-Tama-Audubon-Guthrie-Jasper-Poweshiek-Cass-
Adair-Madison-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
218 PM CDT Mon May 28 2018

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...This afternoon and tonight

Isolated thunderstorms are expected late this afternoon and
evening. A few strong storms are possible, producing small hail
and gusty winds.

Unseasonably hot conditions continue today with heat index values
around 95 to 100 through the evening.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Thunderstorm chances will return between Tuesday afternoon and
Wednesday evening, then again around Saturday. At this time the
threat of severe storms is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

Lee

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
239 PM CDT MON MAY 28 2018

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

0228 PM     TORNADO          2 SE PLOVER             42.85N 94.59W
05/28/2018                   POCAHONTAS         IA   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS A SMALL ROPE
            LANDSPOUT TORNADO TOUCHED DOWN BRIEFLY IN A
            FIELD ABOUT 4 MILES NORTHWEST OF ROLFE,
            KICKING UP SOME DIRT.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
250 PM CDT MON MAY 28 2018

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

0243 PM     HAIL             MAXWELL                 41.89N 93.39W
05/28/2018  E1.00 INCH       STORY              IA   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS QUARTER SIZED HAIL
            FALLING NOW ON THE SOUTH SIDE OF MAXWELL,
            ALONG WITH STRONG WINDS. NO DAMAGE OBSERVED.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
305 PM CDT MON MAY 28 2018

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

0302 PM     HAIL             1 S COLLINS             41.89N 93.31W
05/28/2018  E1.00 INCH       STORY              IA   PUBLIC

            REPORT OF QUARTER SIZED HAIL FALLING.

&&

Special Weather Statement
National Weather Service Des Moines IA
314 PM CDT Mon May 28 2018

IAZ048-049-060>062-282115-
Story-Marshall-Polk-Jasper-Poweshiek-
Including the cities of Ames, Marshalltown, Des Moines, Newton,
and Grinnell
314 PM CDT Mon May 28 2018

...Scattered strong thunderstorms this afternoon...

Scattered thunderstorms are producing small hail and gusty winds
as they move across parts of east central Iowa this afternoon. A
few storms are producing hail up to quarter sized, and an isolated
gust to 60 mph may be possible along with frequent cloud to ground
lightning. Anyone engaging in outdoor activities should stay alert
for approaching storms and seek shelter as soon as appropriate.

Lee