Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service North Platte NE
350 am CDT Tuesday Mar 31 2015

Synopsis...
issued at 350 am CDT Tuesday Mar 31 2015

At 07z...a stationary surface boundary was stretched along the
Kansas-Nebraska border from a low in southern Wisconsin. There was
also a trough and a dewpoint gradient across western Kansas into the
Texas-Oklahoma Panhandle.

&&

Short term...(today and tonight)
issued at 350 am CDT Tuesday Mar 31 2015

Warm frontogenesis across the northern plains today will bring very
warm temperatures and extremely dry conditions to central and
western Nebraska today. Wind is likely to pick up to 15 to 25 miles per hour in
the east as a low level jet develops.

Long term...(wednesday through monday)
issued at 350 am CDT Tuesday Mar 31 2015

The central Continental U.S. Upper level ridge will be in the final phase of it/S
breakdown early Wednesday as a northern steam shortwave rapidly
advances from The Rockies toward the northern plains. In
response...a strong front will dive south across the
plains...reaching the Interstate 80 corridor shortly after 18z
Wednesday. Solid compression heating just in advance of the front
will lead to temperatures in the middle 70s south and east of a
Oneill...to North Platte to Imperial line. The cold push however
will limit highs to the 60s across the northwest sandhills.

The warm temperatures will combine with a moisture challenged lower
troposphere to create conditions favorable for large range fire
growth...especially true as wind speeds are forecast to gust in the
20-30 miles per hour range along and behind the front. Not expecting
widespread rfw relative humidity criteria though /it'll be close/...as enough
moisture advection from a low level jet should help push dew point/S back into the
30-40f range when temperatures are warmest. Noted however behind
the front...TD/S will lower. This may be a case where the front is
concern enough to the fire agencies that a impact based rfw would
still be required. The need will continue to be evaluated.

In addition to the elevated fire concern...isolated storms are still
in the forecast for our far eastern zones Wednesday afternoon.
Southerly flow in advance of the front will advect higher values of
Theta-E into eastern Custer County north through Holt and Boyd
counties. Lapse rates will steepen as the atmosphere becomes
modestly unstable with the approach of the shortwave. Storm
development would then be anticipated along the front during the middle
afternoon hours. Most of the activity should focus east of the
forecast area...however a few higher based storms would be possible
in our area. If storms form...the main threat will be erratic gusty
winds approaching 45 miles per hour.

Beyond Wednesday...an upper level disturbance will follow on the
heals of the cold front producing a chance of light rain into
Thursday across southwest Nebraska. The consensus would suggest
minimal quantitative precipitation forecast. Temperatures will cool in a Post frontal regime
Thursday. Highs in the 50s to lower 60s may be unrealistic if
enough clouds hang around through the day.

Late Thursday into Friday...a positively tilted trough will advance
across The Rockies onto the plains and provide a additional chance
at quantitative precipitation forecast across southwest Nebraska...however the models suggest the
better upper level divergence maximized south and west of the
forecast area. Will continue to cap chances at 40% or less for
now. If precipitation is realized...temperatures may be
sufficiently cool for a mix of rain and snow. Little to no
accumulation would be expected though.

For the weekend...the overall pattern favors the development of a
broad upper level ridge into the central Continental U.S.. temperatures would
once again warm and conditions would dry. Fire concerns will once
again increase.

&&

Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1143 PM CDT Monday Mar 30 2015

Clear skies are expected over the next 24 hours. Winds will be
light and variable through 10 kts through 18z Tuesday...becoming
south at 10 to 20 kts Tuesday afternoon and Tuesday evening.



&&

Fire weather...
issued at 350 am CDT Tuesday Mar 31 2015

Relative humidity is likely to be less than 15 percent in zones 204,
206 and at least a third of zone 208. Wind gusts of 25 miles per hour or higher
are forecast for the Nebraska sandhills and the Panhandle. Wind is
likely to continue into late evening...so we will run the warning
from noon to 11 PM MDT (1 PM to midnight cdt). The relative humidity
is also expected to be less than 15 percent in zones 210 and 219 and
less than 20 percent in zone 209 but wind gusts are expected to be
15-20 miles per hour until after late evening when the relative humidity is
expected to be above 30 percent.

&&

Lbf watches/warnings/advisories...
red flag warning from noon CDT /11 am MDT/ today to 1 am CDT
/midnight MDT/ Wednesday for nez204-206-208.

&&

$$

Synopsis...Springer
short term...Springer
long term...Jacobs
aviation...clb
fire weather...Springer

National Weather Service Glossary of Abbreviations