Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Bismarck ND
913 PM CDT Tuesday Apr 21 2015

Update...
issued at 909 PM CDT Tuesday Apr 21 2015

Current forecast looks very good. Main update will be to let the
red flag warning expire for the James rivet valley.

Update issued at 634 PM CDT Tuesday Apr 21 2015

High pressure continues to clear skies across the region. Winds
will diminish quickly by 8 PM CDT. Just updated current
temperatures and winds.

&&

Short term...(this evening through wednesday)
issued at 315 PM CDT Tuesday Apr 21 2015

Critical fire weather conditions this afternoon highlights the
short term forecast.

Regarding fire weather conditions...see the fire weather
discussion below.

Otherwise...a weak surface high ridge axis will remain in place
across western and central North Dakota through tonight...with a
quiet but cool overnight expected as a result with lows in the
lower 20s. A seasonable day is forecast for Wednesday with highs
generally in the 50s as the surface ridge axis propagates into the
eastern Dakotas through the day. Given good agreement...utilized a
blend of the 12 UTC deterministic and ensemble suites.

Long term...(wednesday night through tuesday)
issued at 315 PM CDT Tuesday Apr 21 2015

A more active period of weather appears likely by the end of the
week.

Wednesday looks cool and dry with northwest flow aloft and surface high
pressure.

Thursday return flow kicks in and upper level ridging breaks down.
West southwest flow aloft will promote Lee cyclogenesis Thursday
through early next week. This will allow several short wave
troughs and associated surface lows to propagate across the
region. The 12 UTC longer range models (gfs and ecmwf) indicate
several rounds of scattered rain showers Friday through Monday.
They vary a fair bit on exact placement of
precipitation...therefore included a broad mention of scattered
showers across the entire area this weekend. Later this week the
short term models should hopefully be able to refine the timing
and placement of precipitation.

Temperatures will slowly moderate late this week into the weekend
with readings in the 60s.

&&

Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 634 PM CDT Tuesday Apr 21 2015

High pressure centered over central North Dakota at 6 PM CDT will
clear skies over the region. VFR at all taf sites through the 00z
taf period.



&&

Fire weather...
issued at 909 PM CDT Tuesday Apr 21 2015

This evening the winds have diminished and the relative humidity
has risen well above critical thresholds. The red flag warning has
been allowed to expire. Winds on Wednesday will be considerably
less than Tuesday. There will be no fire weather concerns on
Wednesday.

&&

Bis watches/warnings/advisories...
none.
&&

$$

Update...warm air advection
short term...ayd
long term...aj
aviation...warm air advection
fire weather...warm air advection

National Weather Service Glossary of Abbreviations