Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Hastings NE
552 PM CDT Sat Aug 1 2015
Short term...(this evening through sunday)
issued at 335 PM CDT Sat Aug 1 2015
Showers and isolated thunderstorms continue mainly to the north of
the forecast area during the afternoon. A gust front is moving south
through the central part of the forecast area.
An upper level wave approaching the area this afternoon and evening
is expected to bring some thunderstorms. There are already a few
cumulus developing in the Panhandle. The short term models bring
convection from the Panhandle toward the forecast area during the
late afternoon into the evening hours. Have kept some probability of precipitation in the
far north with the showers and thunderstorms into the evening hours.
The showers and thunderstorms developing in the Panhandle are
expected to move toward the southeast on the northwest flow during
the evening. Thunderstorms are expected to diminish late this
evening but could linger in the east overnight.
On Sunday a weak cold front develops and slides south into the
forecast area. There is little differences in temperatures with the
front. During the afternoon the models are bringing in a very weak
upper level wave and initiate a few thunderstorms along the front
late in the afternoon. Have kept them near the front and further
east in the forecast area.
Long term...(sunday night through saturday)
issued at 402 PM CDT Sat Aug 1 2015
The big story will be a bit of a cool down Tuesday that will come
with more clouds and chances for thunderstorms. In addition...we can
expect several short waves to track across the forecast area
resulting in frequent chances for showers and thunderstorms. Most of
these thunderstorm events will be fairly hit and miss and there
could be an mesoscale convective system or two that roll through so eventually most folks
should get some rain at one time or another this week.
Monday...best chance of thunderstorms will be across northeastern
zones based on the 12z NAM that indicates a surface trough will be
moving through. The 12z European model (ecmwf) is dry across our forecast area.
Overall...this is a low end chance of thunderstorms and the location
of the surface trough/front will be key in any thunderstorm development.
Tuesday through Friday...our forecast area will be well positioned
to see several short waves move through and with them will come
thunderstorm chances. There will be a general easterly wind
component through much of the period with a surface boundary off to our
south on most days although it will meander back and forth across
portions of our forecast area. The combination of the surface boundary
with easterly flow north of the boundary and upper troughs will
provide the forcing for the several chances of precipitation.
Temperatures will also be cooler north of this boundary so expect
highs a few degrees below normal...generally in the lower 80s.
Aviation...(for the 00z kgri/kear tafs through 00z Sunday evening)
issued at 541 PM CDT Sat Aug 1 2015
An outflow boundary has advanced south of the terminals late this
afternoon and has brought fairly variable winds to the terminals
at this time. Winds are expected to transition south to southwest tonight
and Sunday with another boundary arriving Sunday afternoon. Cannot
rule out convective potential tonight in the vicininty of this
boundary as the low level jet strengthens. On Sunday the surface boundary
may again initiate convection toward the latter taf hours.