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

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 18z tafs through 18z Wednesday afternoon)
issued at 315 PM CDT Tuesday Apr 21 2015

VFR cumulus fields across western and central North Dakota will
continue to lift and scatter through the afternoon and early
evening. Northerly winds gusts of 30-35kts will continue at kjms
through sunset.

&&

Fire weather...
issued at 315 PM CDT Tuesday Apr 21 2015

Red flag warning for the James River Valley area today.

Minimum relative humidity around 25 percent and a northwest wind
gusting to near 40 miles per hour will combine with dry vegetation to result
in another critical fire weather day a across the James River
Valley this afternoon through early evening.

Relative humidity values in the 20s to lower 30s are expected over
many parts of the area Wednesday and Thursday. Winds will be
light for Wednesday...but will increase out of the southeast on
Thursday across western North Dakota...and may result in critical
fire weather conditions. More moisture is expected into the
region Friday through the weekend which should help to at least
temporarily diminish the fire weather threat.



&&

Bis watches/warnings/advisories...
red flag warning until 9 PM CDT this evening for ndz023-025-036-
037-047-048-050-051.

&&

$$

Short term...ayd
long term...aj
aviation...ayd
fire weather...ayd

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