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Area forecast discussion 
National Weather Service Bismarck ND
1241 am CDT Wednesday Apr 1 2015

Update...
issued at 1240 am CDT Wednesday Apr 1 2015

No major changes made for this update.

Light echoes appear on radar across western North Dakota.
However...very dry boundary layer conditions will quickly
evaporate any precipitation before reaching the ground. Only extreme
northwestern North Dakota is expected to see anything measurable
through tomorrow.

Update issued at 931 PM CDT Tuesday Mar 31 2015

Relative humidities have risen to 30 percent or greater across
the warned area...therefore will let the red flag warning for
Tuesday expire as intended. A red flag warning remains in effect
for Wednesday morning through Wednesday evening for strong winds
low humidities and dry vegetation across all of western and
central North Dakota.

Removed thunder across the northwest this evening. Instability is
very weak and best instability aloft not until midnight or after.
Not going to shift thunder mention from this evening to overnight
with such a small probability. Will keep the small chance of
showers but limit quantitative precipitation forecast to a hundredth of an inch. Mesoscale models
do indicate weak reflectivities tracking across the northwest and
north central 06-123 UTC. Otherwise no significant updates are
planned.

Update issued at 644 PM CDT Tuesday Mar 31 2015

Surface low pressure over southeast Alberta with a warm front
through southern Saskatchewan and into northwest through south
central North Dakota. Record high of 76 degrees at Bismarck today.
Dickinson also set a record high with 79 degrees. High level
clouds are beginning to spread into western and central North
Dakota. Relative humidities remain at 15 to 20 percent across most
of the southwest. Red flag warning continues for the southwest
and far south central through around 8 PM mountain time. Will
continue with the red flag warning. Also will continue the rfw for
Wednesday across all of western and central North Dakota.

Updated sky cover to increase clouds west and decrease clouds
east this evening. Updated latest sensible weather elements.

&&

Short term...(this evening through wednesday)

Issued at 410 PM CDT Tuesday Mar 31 2015

Current surface analysis places low over southern Alberta with
frontal boundary dropping down into western Montana. Upper level
analysis places ridge over the northern plains with west/northwest
flow over our area. Southerly low level flow continues over our
area bringing well above to near record temperatures.

For tonight...aforementioned cold front continues its approach...
starting to work its way in towards Wednesday morning.
Otherwise...a weak short wave moving up the ridge as it passes
over our area may bring a few showers to far northern locations.
With some weak instability in place...can not rule out the
possibility of a weak thunderstorm or two.

On Wednesday...front works through the area in the morning with
very windy conditions developing in its wake. Strongest winds will
be mainly over western into parts of central North Dakota where
greatest pressure rises are expected. A few showers can not be
ruled out in the morning over the far north...with little precipitation
if any expected. Dry conditions will combine with the gusty winds
and crispy fuels to bring critical fire weather conditions over
the area (see fire weather discussion below).

Long term...(wednesday night through tuesday)

Issued at 410 PM CDT Tuesday Mar 31 2015

A cooler and quasi-active pattern will dominate the long term
period as deep low pressure sets up over the Hudson Bay bringing
a strong northwesterly flow aloft to North Dakota through at least
the weekend.

Cold front pushes through Wednesday night-Thursday bringing a
chance for light rain/snow and breezy northwesterly winds. Cooler
temperatures and higher relative humidity values than what we are currently
seeing should minimize fire weather concerns during the day
Thursday.

Embedded energy within the flow aloft will maintain chances for
rain or snow Friday-Sunday with more seasonal daytime highs and
lows. Flow becomes more zonal after the weekend with a potential
storm system early next week. Way too much uncertainty to dive
into details at this time...but something Worth watching
considering temperatures aloft would support snow. Higher quantitative precipitation forecast via the
12z GFS...much lower via the 12z European model (ecmwf).

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1240 am CDT Wednesday Apr 1 2015

VFR conditions are expected at all taf sites through the taf
period. Winds will become westerly this morning and increase to
around 30 knots by this afternoon.

&&

Fire weather...

Issued at 347 PM CDT Tuesday Mar 31 2015

Critical fire weather conditions will continue over
southwestern North Dakota into this evening. A strong cold front
will push through the area late tonight into Wednesday morning.
Strong westerly winds will develop behind the front with low
relative humidity values through the day on Wednesday into
Wednesday evening. These will combine with dry fuels throughout
all of western and central North Dakota to bring critical fire
weather conditions.

Cooler temperatures bringing higher relative humidity values will
come to the area on Thursday.

&&

Bis watches/warnings/advisories...
red flag warning from 11 am CDT /10 am MDT/ this morning to 10
PM CDT /9 PM MDT/ this evening for ndz001>005-009>013-017>023-
025-031>037-040>048-050-051.

Wind Advisory from 6 am CDT /5 am MDT/ this morning to 8 PM CDT
/7 PM MDT/ this evening for ndz001>003-009>011-017>021-031>034-
040>045.

&&

$$

Update...aj
short term...jjs
long term...New Hampshire
aviation...aj
fire weather...jjs

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