Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
1237 am CDT Tuesday Mar 31 2015

Update...
issued at 1233 am CDT Tuesday Mar 31 2015

06z aviation discussion updated below.

Update issued at 802 PM CDT Monday Mar 30 2015

Allowed the red flag warning to expire this evening as
temperatures are falling and winds are diminishing quickly. No
major changes are planned to the current forecast as high pressure
settles in.

&&

Short term...(this evening through Wednesday night)
issued at 333 PM CDT Monday Mar 30 2015

Fire weather on Tuesday...and perhaps Wednesday will be the main
concern.

Gusty northwesterly winds have developed over the area behind a
surface trough. While temperatures have exceed expectations...dew
points are not as low as expected. Thus relative humidity values are still above
20 percent. While red flag conditions are not being met...believe
the gusty winds will still cause extreme fire danger. Winds will
diminish tonight...then become southerly on Tuesday. While the air
mass will remain very dry...sustained or frequent gusts of 25 miles per hour
appears best west of the Missouri River valley. While the winds
appear to be marginal...will issue a Fire Weather Watch for the
West River fire zones.

A strong cold front will sweep across the region on Wednesday.
This front could produce an isolated thunderstorm for the eastern
County Warning Area. However the air mass associated with the front is rather
dry...thus will maintain a dry forecast. While relative humidity
values should be higher...strong northwesterly winds of 20 to 30
miles per hour with higher gusts could cause very high to extreme fire danger
Wednesday afternoon. Another fire weather headline could be needed.

Long term...(thursday through monday)
issued at 333 PM CDT Monday Mar 30 2015

A progressive long wave pattern is similarly depicted by most long
range models until about 144 hours and later. At that point the
GFS/UKMET/Gem/cfs show more troffing moving into the western
Continental U.S.. the European model (ecmwf) holds the trough offshore for a few extra periods
before ejecting it inland. Which is correct? Hard to say for sure
with such good agreement outside the European model (ecmwf). However that said the
European model (ecmwf) is often times the first model to show a slower evolution of
the long wave pattern...and therefore cant be totally discounted.

Generally speaking the forecast is mostly dry with just weak
systems expected to affect the area. Better chances for measurable
precipitation might enter the picture toward next weekend as some energy
rides the Flat Ridge across the central Continental U.S.. temperatures
overall should average out near or a bit above normal through the
time period.

&&

Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1233 am CDT Tuesday Mar 31 2015

VFR conditions are expected at all sites through the taf period.
High pressure will settle in briefly tonight before exiting to the
east on Tuesday. As a front moves through on Tuesday light and
variable winds will become more southerly and increase to 10 to 15
kts.

&&

Abr watches/warnings/advisories...
South Dakota...Fire Weather Watch from this afternoon through this evening for
sdz267-268.

Minnesota...none.
&&

$$

Update...mohr
short term...South Dakota
long term...tdk
aviation...mohr

National Weather Service Glossary of Abbreviations