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Area forecast discussion 
National Weather Service Topeka Kansas
1148 PM CDT Friday Oct 9 2015

..update to aviation forecast discussion...

Short term...(this evening through saturday)
issued at 248 PM CDT Friday Oct 9 2015

Post frontal stratus was gradually eroding to the east this
afternoon as the surface ridge builds into the region. Surface
winds become light and variable this evening with mostly clear
skies and lows from the middle 40s east to upper 40s north central
Kansas. Patchy fog just before sunrise still remains a concern as
the latest runs from the NAM and high resolution WRF models have
skies becoming clear aft 06z as sfc condensation pressure deficits
fall near zero through Saturday mid morning. I kept a mention of
patchy fog for areas along and east of a line from Marysville to
Manhattan and Council Grove. Main factor to monitor this evening
are the high clouds dropping southeast over South Dakota. How quickly these
arrive and exit the area will determine the coverage and density
of the fog.

A quick warmup is in store on Saturday as the high pressure shifts
southeast, veering winds to the south at 10 to 15 mph sustained in
the afternoon. 925 mb temps in the 13c-15c range, are progged to mix
down to the surface, resulting in highs from the mid to upper 70s.

Long term...(saturday night through friday)
issued at 248 PM CDT Friday Oct 9 2015

The forecast for Saturday night through Friday remains dry as
northwest flow is expected to prevent any meaningful moisture
return as periodic cold fronts move through the plains. The first
of which is on track to move through Sunday night. A second weaker
front is progged to move through Tuesday night. By the end of the
week, models are a little less certain on the frontal timing and
strength of the high pressure behind the fronts as the European model (ecmwf)
tends to amplify the pattern a little more than the GFS. While the
European model (ecmwf) is generating some light quantitative precipitation forecast Thursday night and Friday, a
lack of large scale forcing with the mean flow remaining to the
north and east of the forecast area will preclude an introduction
of pops at this time.

Highs Sunday continue to look warm and the previous forecast
appears to be in pretty good shape. With the occasional front
moving through next week, temps are expected to not be quite as
warm. But with the pattern still favoring a broad ridge over the
southwest U.S. And troughing along the East Coast, really cold air
looks to stay to the northeast of the forecast area. Therefore
highs are expected to remain above normal with readings in the mid
70 to around 80 for much of the week. After a cool start to
Tuesday with lows in the mid 40s, min temps are expected to remain
in the upper 40s and lower 50s.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1121 PM CDT Friday Oct 9 2015

Terminals should remain VFR for much of the forecast period with
just some high clouds early. Possibly some very shallow ground
fog at the ktop/kfoe terminals near the 12z time frame before
winds begin to mix by 14 or 15z time frame from the south.


Fire weather...
issued at 248 PM CDT Friday Oct 9 2015

Fire weather concerns are a little elevated for Sunday due to the
very warm conditions anticipated and fuels maybe not as green now
that it is early October. With afternoon temps around 90 across
north central KS, min relative humidity values are forecast to be in the 25 to 30
percent range, and around 35 percent across northeast and east
central Kansas. Fortunately winds are not expected to be that strong
with south and southwest winds in the 10 to 15 miles per hour range. However
a cold front is anticipated to move through the area during the
early morning hours Monday. So any fire problems late Sunday could
be enhanced by a wind shift overnight Sunday night.


Top watches/warnings/advisories...


Short term...Bowen
long term...wolters
fire weather...wolters

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