Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Omaha/valley NE
1025 am CDT Monday Mar 17 2014
Short term...(today through wednesday)
issued at 325 am CDT Monday Mar 17 2014
Rather active period in the short term as progressive upper flow
brings a series of weather systems across the region. Rapid
changes in temperatures and strong winds will be the primary
focus in this forecast which is typical of the transition month
Strong upper wave coming into the Pacific northwest early this
morning will enhance Lee side troughing and cyclogenesis over the
western High Plains this afternoon. As the pressure gradient
tightens today in advance of this system very warm and dry
conditions will spread north on gusty south winds. Extreme fire
danger is expected this afternoon across most of eastern Nebraska
and as a result a red flag warning will be in effect into early
Eastern Nebraska and southwest Iowa will remain in the warm
sector tonight ahead of a strong cold front. South winds will
diminish as the front approaches the area late tonight then
switch to the northwest and intensify behind the front on Tuesday.
Along with the strong winds some precipitation is also likely to
spread across the area on Tuesday. Rain showers are expected
initially with the rain changing to snow as the cold air deepens.
Temperatures will have a big impact on winter weather potential
with the combination of wind and snow but a lot of uncertainty
regarding the timing of the cold air so will hold off on any
specific headline at this time and broadbrush in hazardous weather
outlook. This will be a fast moving system with the best forcing
located east of the area by Tuesday evening with decreasing snow
potential as the cold air comes into eastern parts of the County Warning Area.
Winds diminish Tuesday night as the deep surface low tracks off to
the northeast toward the Great Lakes and the pressure gradient
relaxes across the area. Another strong short wave trough moves
across the plains region on Wednesday. Some potential for a few
rain showers with this system as a 500 mb pocket of cold air will
help with destabilization. Only slight probability of precipitation included at this time
for Wednesday afternoon.
Long term...(wednesday night through sunday)
issued at 325 am CDT Monday Mar 17 2014
Short wave ridging moves into the plains region Wednesday night
in advance of another trough coming into the Pacific northwest.
This will set the stage for another round of warming on Thursday.
After this it appears the area will be under the influence of a
stronger northern stream flow with temperatures expected to stay
in a normal range with less wide spread swings from day to day.
Looks generally dry for the most part during this time.
Aviation...(12z tafs for kofk...klnk and koma.)
Issued at 615 am CDT Monday Mar 17 2014
Surface winds should increase across eastern Nebraska into
midday...generally from the south or south southwest.
However...if conditions mix deeply enough winds could obtain more
of a SW component providing more cross wind potential for
runways...although that risk would appear higher at kofk and
possibly klnk. Otherwise VFR conditions are expected at taf sites
through 18/12z. Decreasing surface winds tonight along with a
continued strong low level jet could provide wind shear potential
and mention was maintained in 12z forecast. An approaching
front/upper trough will bring deteriorating conditions on
Tuesday...but probably not until after 12z.
issued at 1020 am CDT Monday Mar 17 2014
Temperatures will climb to around 70 this afternoon with
dewpoint temperatures in the upper teens to lower 20s culminating
in relative humidity values ranging from 15 to 20 percent across
the area. In addition...south to southwest winds gusting 30 to 35
miles per hour are expected. The combination of these conditions along with
very dry fuels will create very high to extreme fire danger this
afternoon across the area. Controlled Burns are highly
NE...red flag warning until 8 PM CDT this evening for nez011-012-
Iowa...Fire Weather Watch until 8 PM CDT this evening for iaz043-055-
Red flag warning until 8 PM CDT this evening for iaz079-080-090-