Winter Weather Advisory 3, NWS Des Moines, IA

Black Hawk County, IA, Boone County, IA, Bremer County, IA, Butler County, IA, Calhoun County, IA, Cerro Gordo County, IA, Dallas County, IA, Emmet County, IA, Franklin County, IA, Greene County, IA, Grundy County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Humboldt County, IA, Jasper County, IA, Kossuth County, IA, Marshall County, IA, Palo Alto County, IA, Pocahontas County, IA, Polk County, IA, Poweshiek County, IA, Sac County, IA, Story County, IA, Tama County, IA, Webster County, IA, Winnebago County, IA, Worth County, IA, Wright County, IA

940 
WWUS43 KDMX 192228
WSWDMX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Des Moines IA
428 PM CST Tue Jan 19 2021

...Blowing Snow and Slick Roads...

.Strong northwest winds gusting to near 40 mph at times, combined
with snow showers and snow already on the ground, will create 
areas of blowing snow this evening. Visibility will be reduced to
below a half mile at times, and the blowing snow will melted and 
refreeze on roadways leading to icy travel conditions.

IAZ026>028-036>039-046>050-059>062-200200-
/O.EXA.KDMX.WW.Y.0003.000000T0000Z-210120T0200Z/
Franklin-Butler-Bremer-Hamilton-Hardin-Grundy-Black Hawk-Greene-
Boone-Story-Marshall-Tama-Dallas-Polk-Jasper-Poweshiek-
Including the cities of Hampton, Parkersburg, Clarksville, 
Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, 
Webster City, Iowa Falls, Eldora, Ackley, Grundy Center, 
Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, 
Jefferson, Boone, Ames, Marshalltown, Tama, Toledo, Traer, 
Dysart, Gladbrook, Perry, Waukee, Adel, Des Moines, Newton, 
and Grinnell
428 PM CST Tue Jan 19 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 8 PM CST THIS
EVENING...

* WHAT...Snow and blowing snow. Winds gusting over 40 mph at
  times. Additional snow accumulations of up to one inch. 
  Visibility reduced to below half a mile at times in blowing 
  snow.

* WHERE...North central and central Iowa.

* WHEN...Until 8 PM CST this evening.

* IMPACTS...Rapidly changing visibility slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

IAZ004>007-015>017-023>025-033>035-200200-
/O.CON.KDMX.WW.Y.0003.000000T0000Z-210120T0200Z/
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-
Including the cities of Estherville, Algona, Forest City, 
Lake Mills, Northwood, Manly, Emmetsburg, Garner, Britt, Kanawha,
Mason City, Clear Lake, Pocahontas, Laurens, Rolfe, Fonda, 
Gilmore City, Humboldt, Eagle Grove, Clarion, Belmond, Sac City, 
Lake View, Odebolt, Wall Lake, Schaller, Early, Rockwell City, 
Manson, Lake City, Pomeroy, and Fort Dodge
428 PM CST Tue Jan 19 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 PM CST THIS
EVENING...

* WHAT...Snow and blowing snow. Winds gusting over 40 mph at
  times. Additional snow accumulations of up to one inch. 
  Visibility reduced to below half a mile at times in blowing 
  snow.

* WHERE...North central and central Iowa.

* WHEN...Until 8 PM CST this evening.

* IMPACTS...Rapidly changing visibility slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

936 
WWUS43 KDMX 200003
WSWDMX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Des Moines IA
603 PM CST Tue Jan 19 2021

...Blowing Snow and Slick Roads...

.Strong northwest winds gusting to near 40 mph at times, combined
with snow showers and snow already on the ground, will create
areas of blowing snow this evening. Visibility will be reduced to
below a half mile at times, and the blowing snow will melted and
refreeze on roadways leading to icy travel conditions.

IAZ004-005-015-023-024-033>035-046-200115-
/O.CAN.KDMX.WW.Y.0003.000000T0000Z-210120T0200Z/
Emmet-Kossuth-Palo Alto-Pocahontas-Humboldt-Sac-Calhoun-Webster-
Greene-
Including the cities of Estherville, Algona, Emmetsburg, 
Pocahontas, Laurens, Rolfe, Fonda, Gilmore City, Humboldt, 
Sac City, Lake View, Odebolt, Wall Lake, Schaller, Early, 
Rockwell City, Manson, Lake City, Pomeroy, Fort Dodge, 
and Jefferson
603 PM CST Tue Jan 19 2021

...WINTER WEATHER ADVISORY IS CANCELLED...

Winds have begun to subside with blowing snow ending and improving
visibilities, therefore the advisory is cancelled. 

$$

IAZ006-007-016-017-025>028-036>039-047>050-059>062-200200-
/O.CON.KDMX.WW.Y.0003.000000T0000Z-210120T0200Z/
Winnebago-Worth-Hancock-Cerro Gordo-Wright-Franklin-Butler-Bremer-
Hamilton-Hardin-Grundy-Black Hawk-Boone-Story-Marshall-Tama-
Dallas-Polk-Jasper-Poweshiek-
Including the cities of Forest City, Lake Mills, Northwood, 
Manly, Garner, Britt, Kanawha, Mason City, Clear Lake, 
Eagle Grove, Clarion, Belmond, Hampton, Parkersburg, Clarksville,
Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, 
Webster City, Iowa Falls, Eldora, Ackley, Grundy Center, 
Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, Boone, 
Ames, Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, 
Perry, Waukee, Adel, Des Moines, Newton, and Grinnell
603 PM CST Tue Jan 19 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 8 PM CST THIS
EVENING...

* WHAT...Primarily blowing snow. Winds gusting over 40 mph at
  times. Visibility reduced to below half a mile at times in 
  blowing snow.

* WHERE...North central and central Iowa. This will occur mainly
  in open rural areas. Locations in and near urban centers will
  remain largely unaffected. 

* WHEN...Until 8 PM CST this evening.

* IMPACTS...Rapidly changing visibility slippery road conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

699 
WWUS43 KDMX 200111
WSWDMX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Des Moines IA
711 PM CST Tue Jan 19 2021

IAZ006-007-016-017-025>028-036>039-047>050-059>062-200215-
/O.CAN.KDMX.WW.Y.0003.000000T0000Z-210120T0200Z/
Winnebago-Worth-Hancock-Cerro Gordo-Wright-Franklin-Butler-Bremer-
Hamilton-Hardin-Grundy-Black Hawk-Boone-Story-Marshall-Tama-
Dallas-Polk-Jasper-Poweshiek-
Including the cities of Forest City, Lake Mills, Northwood, 
Manly, Garner, Britt, Kanawha, Mason City, Clear Lake, 
Eagle Grove, Clarion, Belmond, Hampton, Parkersburg, Clarksville,
Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, 
Webster City, Iowa Falls, Eldora, Ackley, Grundy Center, 
Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, Boone, 
Ames, Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, 
Perry, Waukee, Adel, Des Moines, Newton, and Grinnell
711 PM CST Tue Jan 19 2021

...WINTER WEATHER ADVISORY IS CANCELLED...

Winds have gradually subsided with visibilities improving across
central Iowa, therefore the advisory is cancelled. 

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

Area Forecast Discussion
National Weather Service Des Moines IA
213 PM CST Tue Jan 19 2021

.DISCUSSION.../Tonight through Tuesday/
Issued at 212 PM CST Tue Jan 19 2021

A final round of light wintry precip lingers over the area this
afternoon with some scattered snow showers evident on radar.
Any accumulations have been light, but still enough to create
some road impacts and brief visibility reductions in northern
Iowa. The responsible shortwave trough axis swings through late
this afternoon and evening. The attendant surface low/front
features a strong isallobaric push which will promote gusty
northwest winds through the rest of the afternoon into the evening
hours. Wind gusts may approach 40 mph at times and may create
some patchy blowing snow. Winds gradually relax later this evening
into the overnight hours. Skies continue to clear out in the
subsidence regime trailing the departing shortwave. Model guidance
came in considerably cooler for tonight, so forecast lows have
been dropped into the single digits and teens. Still some
uncertainty that winds will be calm enough/skies clear enough for
maximum radiational cooling to occur.

A brief warmup is still on track as a shortwave ridge builds over
the region tomorrow. Gusty southwest winds will mix down an axis
of warmer 925-850mb temps beneath the upper ridge. NBM has
trended a bit cooler for tomorrow, but is likely being dragged
down by a stark bimodal distribution in the temperature guidance.
Raw guidance is considerably cooler than MOS output, in excess of
10 degrees in some areas. Opted to stick with persistence and stay
on the warm side tomorrow given the favorable setup and plentiful
sunshine, which pushes highs into the upper 30s north and east to
near 50 in our far southwest. A series of dry frontal passages
Wednesday night and Thursday will gradually knock down
temperatures, although the coldest air does not arrive until later
Thursday into Friday. Highs Friday only make it into the teens at
20s. Lows may dip below zero in north central Iowa Friday night
as the core of a 1030mb surface high slides through, however the
possibility of increasing upper level cloud cover casts some doubt
at this point.

The weekend into early next week still looks active, although it
remains to be seen just how impactful it may be for central Iowa.
A large trough digs down the west coast into nearly the Baja
region, then pivots across the central Plains Sunday into Monday.
Last few model runs have deamplified this wave a bit as it
traverses the region, and hang the parent trough further back as
it is reinforced by another shortwave dropping south down the west
coast. We will see precipitation chances increase by late
Saturday into Sunday as a warmer, moist airmass is advected
northward. A broad swath of precip may develop as the air is
lifted isentropically to the north of a warm front stretched
across northern Missouri. Models have also trended a bit cooler
with thermal profiles through Sunday, which makes sense given the
weakened nature of the approaching upper wave. Thus now
forecasting mostly snow ptypes north of I-80 and more of a mixed
bag of ptypes in southern Iowa. The sporadic loss of ice in the
cloud layer may also come into play and further complicate the
ptype forecast. Another wave of wintry precipitation is possible
as the main wave kicks out by mid-week, but substantial model
spread becomes a significant hindrance to forecast confidence by
that period.

&&

.AVIATION.../For the 18Z TAFS through 18Z Wednesday afternoon/
Issued at 1119 AM CST Tue Jan 19 2021

Main forecast challenges through the current TAF period is cigs
and impacts from -SN activity today. Most -SN should remain over
north central Iowa, but may tempo drop visby down to 1sm. Most
cigs currently reside in VFR/MVFR range. Some pockets of IFR are
possible in north central Iowa this afternoon as well. Winds will
strengthen considerably out of the west over the next few hours.
Gusts in excess of 30 kts may be common before relaxing a bit
after sunset. Skies clear out overnight and should stay VFR
through tomorrow.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

DISCUSSION...Martin
AVIATION...Martin

Hazardous Weather Outlook
National Weather Service Des Moines IA
401 AM CST Tue Jan 19 2021

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-
081>086-092>097-201200-
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-Dallas-Polk-Jasper-
Poweshiek-Cass-Adair-Madison-Warren-Marion-Mahaska-Adams-Union-
Clarke-Lucas-Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-
Appanoose-Davis-
401 AM CST Tue Jan 19 2021

This Hazardous Weather Outlook is for much of central Iowa.

.DAY ONE...Today and tonight

Areas of light freezing drizzle or light snow early morning, and
additional chances for light snow central and northeast later
today, may produce slick roads with a light coating of snow or
ice today.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Wintry precipitation is expected to spread into the region this
weekend and might impact travel starting Saturday afternoon.
Details on precipitation type and amounts will be better assessed
in the coming days.

.SPOTTER INFORMATION STATEMENT...

Spotters will not be needed.

Small

Special Weather Statement
National Weather Service Des Moines IA
952 AM CST Tue Jan 19 2021

IAZ004>007-015>017-023-024-191900-
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-
Including the cities of Estherville, Algona, Forest City,
Lake Mills, Northwood, Manly, Emmetsburg, Garner, Britt, Kanawha,
Mason City, Clear Lake, Pocahontas, Laurens, Rolfe, Fonda,
Gilmore City, and Humboldt
952 AM CST Tue Jan 19 2021

Scattered snow showers will move through north central Iowa over
the late morning into early afternoon hours. While accumulations
are expected to be light, brief reductions in visibility to a mile
or less may occur along with pockets of slick travel conditions.
Motorists are advised to use caution.

Special Weather Statement
National Weather Service Des Moines IA
136 PM CST Tue Jan 19 2021

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-
081>086-092>097-200000-
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-Dallas-Polk-Jasper-
Poweshiek-Cass-Adair-Madison-Warren-Marion-Mahaska-Adams-Union-
Clarke-Lucas-Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-
Appanoose-Davis-
Including the cities of Estherville, Algona, Forest City,
Lake Mills, Northwood, Manly, Emmetsburg, Garner, Britt, Kanawha,
Mason City, Clear Lake, Pocahontas, Laurens, Rolfe, Fonda,
Gilmore City, Humboldt, Eagle Grove, Clarion, Belmond, Hampton,
Parkersburg, Clarksville, Shell Rock, Greene, Aplington, Allison,
Dumont, Waverly, Sac City, Lake View, Odebolt, Wall Lake,
Schaller, Early, Rockwell City, Manson, Lake City, Pomeroy,
Fort Dodge, Webster City, Iowa Falls, Eldora, Ackley,
Grundy Center, Reinbeck, Conrad, Dike, Wellsburg, Waterloo,
Cedar Falls, Denison, Carroll, Jefferson, Boone, Ames,
Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, Audubon,
Exira, Guthrie Center, Panora, Bayard, Casey, Perry, Waukee,
Adel, Des Moines, Newton, Grinnell, Atlantic, Greenfield, Stuart,
Adair, Fontanelle, Winterset, Earlham, Indianola, Norwalk,
Carlisle, Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola,
Chariton, Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr,
Lamoni, Leon, Corydon, Seymour, Allerton, Humeston, Centerville,
and Bloomfield
136 PM CST Tue Jan 19 2021

Strong west to northwest winds develop behind a passing front this
afternoon. Gusts of up to 40 mph are possible into the early
evening hours. Patchy blowing snow may be observed in portions of
north central into central Iowa. Motorists are advised to use
caution in areas of blowing snow and reduced visibility.