Another upper level weather system produced light to moderate snowfall in eastern Nebraska and southwest Iowa. Snowfall amounts with this storm were generally 1-3 inches.
Every event with a place to put it; 9 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS OAX wrote it up.
Another upper level weather system produced light to moderate snowfall in eastern Nebraska and southwest Iowa. Snowfall amounts with this storm were generally 1-3 inches.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Omaha, NE wrote its last area forecast discussion before the first event at Feb 21, 11:33 PM CST, 27 minutes earlier.
Area Forecast Discussion
National Weather Service Omaha/Valley NE
1133 PM CST Wed Feb 21 2018
.UPDATE...
Issued at 902 PM CST Wed Feb 21 2018
A short-wave trough presently over the southern Plains is
promoting a strengthening downstream belt of warm advection across
the central Plains into mid-MO Valley which is being manifest as
increasing echoes in mosaic radar data. 00z OAX/TOP soundings
revealed a considerable amount of dry air in the low levels which
will have to be overcome before precipitation begins to reach the
ground. Latest convection-allowing model guidance and 00z NAM data
indicate light snow developing within the next 2-3 hours mainly
south of I-80 and gradually spreading northeast through daybreak
Thursday. Snow accumulations with this initial wave of
precipitation (though about 8 AM Thu) will range from less than
half an inch generally north of I-80 to around 2" over southeast
NE.
The initial warm-advection-related precipitation should largely
shift to the east of the area by mid morning Thu with forecast
soundings indicating a developing warm nose aloft and loss of ice
in the dendritic-growth zone. The net result is a transition of
any light, lingering precipitation to freezing drizzle or light
freezing rain. The exception is over northeast NE where
predominant precipitation type may remain snow.
By late tomorrow afternoon into evening, large-scale forcing for
ascent re-intensifies in response to the approach of the next
disturbance aloft. At that time, we would expect to see an
increase in precipitation rates with predominantly freezing rain
along and south of I-80 with a transition to sleet and then snow
northward into northeast NE and west-central IA.
The current forecast appears in reasonably good shape and we have
made only minor adjustments.
&&
.SHORT TERM...(Tonight through Saturday)
Issued at 447 PM CST Wed Feb 21 2018
Timing precip and location of dominate type late tonight through
Thursday evening is initial concern followed by Snow event on
Saturday.
Regional mosaic already showing batch of precip beginning to lift
northward into eastern KS. HRRR/RAP13 indicate activity should
reach the southern CWA shortly before midnight. Per RAP13 MaxT
aloft prog...there will definitely be a fine line separating
freezing/frozen precip. As of now, appears likely snow will be the
predominate type between midnight tonight and early Thursday
morning as it advances northward through the CWA. However, as
layer MaxT go above freezing from south to north, and feeder-
seeder process begins to weaken, expect snow to give way to light
freezing drizzle from south to north, expanding across the rest
of the CWA the remainder of the day into the evening hours. Snow
accumulations should be relatively even over the CWA ranging from
about 1 to 2 inches. Brunt of ice accumulations will be found over
southwest IA south of I-80 with anywhere from one to two tenths
possible. Over the rest of the CWA, five hundredths to a tenth
looks possible. Given this, will post a Winter Weather Advisory to
be in effect from late tonight through Thursday evening.
Turning to Saturday, a potent system lifting into the central Plains
will be the focus for the next snow accumulation event over the
region. Synoptic scale forcing will increase substantially as
500mb hgt falls of 15dam precedes a quite potent vort max as it
pushes across NE/KS. Associated precip activity will develop
within the warm sector of the surface reflection which is progged
to be in western KS 12z Saturday. The GFS and CMC are in rather
good agreement depicting the axis of heaviest lining up from
southwest NE to southeast SD, just to the left of the 500mb HFC
track. And as of now, there appears to be a distinct possibility
for significant snow accumulations over the northern CWA where
dendritic omega will be maximized...per the GFS...advertising over
40 microbars of lift.
.LONG TERM...(Saturday night through Wednesday)
Issued at 447 PM CST Wed Feb 21 2018
GFS/CMC in agreement extended periods will be dry from Sunday
through at least Tuesday before the next chance for precip. Tuesday
night and Wednesday, model show a cold front dropping into the
central Plains with the possibility a snow/rain mix event.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1132 PM CST Wed Feb 21 2018
Radar data and surface observations indicate light snow beginning
to fall across portions of south-central and southeast NE with the
snow expected to overspread much of eastern NE and southwest IA
through daybreak on Thursday. Periods of moderate snow are
possible, especially at KOMA and KLNK where visibilities may fall
to a mile or so. Ceilings should also continue to lower with
prevailing MVFR conditions developing after 12z Thursday. Snowfall
should taper off by mid morning on Thursday with a phase change
to freezing drizzle possible at KOMA and KLNK through much of the
day. Precipitation rates are expected to increase again by late
afternoon into evening with snow expected to be the predominant
weather at KOFK. At KOMA and KLNK, a mixture of freezing rain and
snow is possible. Precipitation should end by mid to late evening
with a continuation of MVFR ceilings.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Winter Weather Advisory from 3 AM Thursday to midnight CST
Thursday night for NEZ034-044-045-050>053-065>068-090>093.
Winter Weather Advisory from 3 AM to 6 PM CST Thursday for
NEZ078-088-089.
Winter Weather Advisory from 6 AM Thursday to midnight CST
Thursday night for NEZ012-015-017-018-031>033-042-043.
Winter Weather Advisory from 6 AM to 6 PM CST Thursday for
NEZ011-016-030.
IA...Winter Weather Advisory from 3 AM Thursday to midnight CST
Thursday night for IAZ043-055-056-069-079-080-090-091.
&&
UPDATE...Mead
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...MeadHazardous Weather Outlook National Weather Service Omaha/Valley NE 507 PM CST Wed Feb 21 2018 IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034- 042>045-050>053-065>068-078-088>093-221315- Monona-Harrison-Shelby-Pottawattamie-Mills-Montgomery-Fremont- Page-Knox-Cedar-Thurston-Antelope-Pierce-Wayne-Boone-Madison- Stanton-Cuming-Burt-Platte-Colfax-Dodge-Washington-Butler- Saunders-Douglas-Sarpy-Seward-Lancaster-Cass-Otoe-Saline- Jefferson-Gage-Johnson-Nemaha-Pawnee-Richardson- 507 PM CST Wed Feb 21 2018 This Hazardous Weather Outlook is for portions of southwest Iowa...west central Iowa...east central Nebraska...northeast Nebraska and southeast Nebraska. .DAY ONE...Tonight and Thursday Light snow is expected to spread from south to north over eastern Nebraska and southwest Iowa late tonight. On Thursday, the light snow will give way to freezing drizzle through the majority of the day. Snow accumulations should be fairly uniform with 1 to 2 inches possible. However, the bulk of ice accumulations will be found over southwest IA south of I-80 with anywhere from one to two tenths possible. Over the rest of eastern Nebraska and west-central Iowa, five hundredths to a tenth looks possible. .DAYS TWO THROUGH SEVEN...Thursday night through Wednesday Light ice accumulations will be possible over the outlook area Thursday night. A strong storm system pushing across the region will be the focus for the next snow event on Saturday. As of now, it appears that significant snow accumulations will be found over northeast Nebraska, with light amounts across the rest of southeast Nebraska and southwest Iowa. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed through Tuesday.
The national radar mosaic for the moment the first event began.
9 winter weather. Local standard time, as filed.
An observer reported 3 inches of snow at Lincoln. Throughout the metro Lincoln area there was 2-3 inches of snow.
A CoCoRaHS observer measured 2.5 inches of snow at Gretna. Snowfall amounts across Sarpy County ranged from 1.5 inches to 2.5 inches.
Snowall 2 miles southeast of Boys Town amounted to 3 inches. Throughout Douglas County snowfall ranged from 0.7 inch at Eppley Airfield to 2 to 3 inches across western Douglas County.
An observer reported 1.5 inches of snow in Blair.
At 2 miles south of Wahoo, 1.6 inches of snow fell. There was 1 to 2 inches of snow that fell over the remaining parts of Saunders County.
An observer reported 1.2 inches of snow at David City.
At Fairbury, 2.6 inches of snow fell. Other locations in Jefferson County included 1.5 inches at Daykin, and 2.5 inches 3 miles west of Endicott.
A report from Johnson was 1 inch of snow.
An observer 1 mile north of Beatrice measured 2 inches of snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nebraska in 2018Every state in 2018This day in weather historyWarnings in Nebraska, February 2018
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 742711, 742714, 742724, 742725, 742728, 742733, 742735, 742736, 742740.