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Area forecast discussion 
National Weather Service Bismarck ND
1113 am CDT Tuesday may 5 2015


Issued at 1112 am CDT Tuesday may 5 2015

No major changes to the previous forecast with this issuance.

Dry today followed by increasing chances for showers and isolated
thunderstorms later this evening into the overnight as lead shortwave
impulses lift north through the Dakotas. Best chances through 12z
will be across the south...with the most favorable area of
T-storms along to south of i94.

Update issued at 615 am CDT Tuesday may 5 2015

Latest suite of satellite imagery show a couple of weak shortwaves
in eastern Montana/western North Dakota shifting east with time.
Partly to mostly cloudy conditions being generated with low to middle
level clouds streaming north. Current forecast remains on track.


Short term...(today and tonight)
issued at 407 am CDT Tuesday may 5 2015

Focus in the short term is on fire weather concerns this afternoon
and the chances for precipitation tonight.

Have upgraded the Fire Weather Watch to a red flag warning for
this afternoon. Relative humidity as low as 20 percent and strong
winds gusting up to 30 miles per hour...with dry conditions in place will
create critical fire weather conditions.

Overall model consensus on the upper level impulse ahead of the
deep 500 mb trough over the West Coast remains in good agreement.
The 00 UTC GFS run brings precipitation in the earliest with a
chance across south central North Dakota by Wednesday 06 UTC. With
moderate cape values in place went ahead and kept the chances for
thunderstorms in the forecast for late tonight. By 12 UTC
Wednesday the European model (ecmwf) and NAM runs...along with the GFS bring
precipitation into North Dakota. However...with zero cape and
very little bulk shear have kept any mention of thunderstorms out
of the forecast for late Tuesday night early Wednesday morning.

Long term...(wednesday through monday)
issued at 407 am CDT Tuesday may 5 2015

A widespread wet period continues to evolve Wednesday through
Thursday night followed by a break Friday. The latest rainfall totals
per wpc through Thursday night ranges from 0.50 inches to 1.3
inches across western and central North Dakota. Another system
slowly moves into the Central Plains Saturday and edges closer to
North Dakota by late in the weekend into early next week. This
places the highest chances of precipitation across southern North

The current water vapor imagery loop shows two significant shortwaves
associated with the southern branch of the jet stream which will
affect North Dakota. The first shortwave was located over southeast
New Mexico...with the second shortwave trough associated with the
main upper low over Arizona. The initial shortwave will lift north
during the day Wednesday with widespread showers and a chance for
thunderstorms. This will be followed by the main upper low Wednesday
night through Thursday evening. Likely to categorical probability of precipitation forecast
across western and central North Dakota Wednesday through Thursday
evening...before tapering off from west to east Thursday night.
Instability is present with both shortwaves...however the highest
cape of around 280 j/kg coincides with 0-6m bulk shear of 25kt from
18z Wednesday through 06z Thursday...especially in the southern
James River Valley. This should represent the best chances for
thunderstorms. At this time expecting thunderstorms to remain below
severe thresholds which is in line with the current Storm Prediction Center convective
outlook. Will continue to monitor for any changes.

The system departs later Thursday night with a cooler and drier day
Friday. The next system looks to spread a chance of showers into the
southwest and far south central Friday night into Saturday...then
hover near the southern border Saturday night before showing a
northward push Sunday into Monday across southern North Dakota.
Cooler temperatures at night during the Friday through Monday time
frame may lead to areas of frost...especially central and north
where less clouds and precipitation are forecast. Highs in the 50s
can be expected Friday through Monday with lows in the middle to upper


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 610 am CDT Tuesday may 5 2015

Low pressure system pushing northeast into western and central
North Dakota will increase southeasterly winds through the day
Tuesday. Cloud cover will also increase today with some
potentially MVFR ceilings moving into kbis...kdik...and kjms between
00z and 06z on Wednesday. There is a chance of rain toward the end
of the 12 UTC taf cycle at kdik...kbis...and kjms. However
confidence in the timing of showers and potentially a thunderstorm
is not high enough to put in the taf.


Fire weather...
issued at 407 am CDT Tuesday may 5 2015

Have upgraded the Fire Weather Watch to a red flag warning for
this afternoon. Relative humidity as low as 20 percent and strong
winds gusting up to 30 miles per hour...with dry conditions in place will
create critical fire weather conditions.


Bis watches/warnings/advisories...
red flag warning until 7 PM CDT this evening for ndz004-005-012-



Update...New Hampshire
long term...Kansas

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