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Area forecast discussion 
National Weather Service North Platte NE
546 PM CST Monday Jan 26 2015

issued at 231 PM CST Monday Jan 26 2015

Record or near warm weather continues Tuesday then a
series of cold fronts pass through western and north central
Nebraska Wednesday and beyond returning the region to near normal.
The models present a chance of light snow Saturday as moisture and a
portion of an upper level storm across the southwestern U.S. Lifts north into
the cntl plains.


Short term...(this evening through tuesday)
issued at 231 PM CST Monday Jan 26 2015

Main weather concerns for western Nebraska through Tuesday evening are
temperatures and elevated fire threat as near record maximum temperatures are
expected Tuesday. In the meantime...continued mostly clear
conditions area wide through tonight as forecast soundings indicate
dry air extending from the surface to near the tropopause. With
winds diminishing after sunset Monday...expect the atmosphere to at
least partially decouple. Kept min temperatures lower in the Platte River
valley compared to the rest of the forecast area...with middle 20s and
near 30 respectively. Overall...went above guidance for min temperatures
Tuesday morning as warm air advection at 850 hpa will be underway
toward dawn. The Euro...NAM...and GFS show 850 hpa temperatures of 15 to
17c along and west of U.S. Highway 83 at 27/12z.

During the day Tuesday...full sunshine is expected across western
Nebraska along with west winds. The wind profile stays
unidirectional through at least 700 hpa...setting up for a
downsloping scenario...especially for the western half of the
forecast area. Bumped up maximum temperatures a couple degrees compared to
previous forecast...which is consistent with mav guidance. NAM and
GFS forecast soundings show middle 70s for klbf...which is not entirely
out of the question. Given lighter winds Tuesday as compared to
Monday and full mixing not anticipated...stayed modest with lower
70s. Across north central Nebraska...850 hpa temperatures stay cooler
/mainly in the 12 to 15c range/ and have kept maximum temperatures in the 60s.
With forecast surface dew points in the upper 20s and lower 30s...relative humidity
values will be approaching critical levels...primarily across the
southern Panhandle and southwest Nebraska. Wind is expected to stay
generally at or under 10 knots to alleviate any major fire threat.
However...with any downsloping event...there is the potential for
drier air and/or higher winds during the afternoon and will keep the
elevated fire threat mentioned.

Long term...(tuesday night through monday)
issued at 231 PM CST Monday Jan 26 2015

Tuesday night through Thursday...a weak Pacific cold front moves
through Tuesday night which should keep the atmosphere well mixed
for lows in the 30s. This presents a windy day for Wednesday and the
model consensus indicates north winds around 25 miles per hour. There is still
plenty of warm air available for highs in the 50s to lower 60s.

A stronger push of cold air will be moving in Wednesday night as a
new storm drops into the Midwest and begins to strengthen. This
storm will draft Arctic high pressure across Alaska where it is 50
below zero this morning. Fortunately the cold side of the high will
pass well east of the forecast area. Highs in the low to middle 40s are
forecast and this is close to the ecm and NAM models.

The only significant cloud cover develops Wednesday night and the
NAM model derived radar product suggests at least sprinkles and
flurries with the cold front. Probability of precipitation may be raised in later forecasts
as warranted by the other models which show limited moisture at the
850-700 mb levels.

Friday through Monday...the models today show reasonably good
agreement with Arctic high pressure across Alaska moving south
through the northern plains and into the upper Midwest Saturday through
Monday. This should cool the forecast area into the 30s as the high
centers across eastern ND and Minnesota. Friday would be the warmest day as
winds become south with low pressure across the Dakotas ahead of the
Arctic front.

The models are wobbling a bit Saturday. Today the models drag a
portion of an upper low and its moisture across the southwestern U.S. North
into Nebraska. This presents an opportunity for light snow Saturday south
of Highway 20. The ecm and GFS models suggest an inch or two. Probability of precipitation
are just 20 percent but would almost certainly increase if the
models are consistent in the future.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 545 PM CST Monday Jan 26 2015

VFR conditions for the klbf and kvtn terminals the next 24 hours.
In fact...clear skies are forecast with light westerly winds
below 10 kts.


Lbf watches/warnings/advisories...


short term...ds/Taylor
long term...cdc

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