Area Forecast Discussion
Issued by NWS Aberdeen, SD

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KABR 170528 AAC

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1228 AM CDT Mon Apr 17 2017

Issued at 1225 AM CDT Mon Apr 17 2017

See updated aviation discussion below.

UPDATE Issued at 806 PM CDT Sun Apr 16 2017

Forecast is on track this evening. Allowed the Red Flag Warning to
expire. Winds have diminished to 10 to 20 mph and RH is


.SHORT TERM...(This Evening through Monday Afternoon)
Issued at 315 PM CDT Sun Apr 16 2017

Temperatures in the 60s and dewpoints in the teens to low 20s have
combined with gusty westerly winds of 15-25mph and a few gusts near
35 mph to keep the Red Flag Warning going for fire weather zones
039, 046, 268, 269, 271, 272 and 273. RH values are in the 16 to 25
percent range across the entire area. The Red Flag Warned area is
directly south of the a west to east oriented cold front stretched
just north of the ND/SD border this afternoon. Temperatures in ND
have been 5-10F cooler, with dewpoints in the upper 20s to low 30s.
This is while the main area of high pressure has shifted from west
central SD down through eastern NE.

Some of the CAM solutions continue to show the potential for shower
development near or south of Lyman County around 23Z, and clipping
our eastern counties mainly 02-05Z Monday near the sfc trough set up
across the area. Continued the idea of just sprinkles, with the
coverage area shifted slightly south. Otherwise large high pressure
across south central Canada will slowly sink across the Dakotas
overnight, and slide over MN by mid day Monday. Look for a warm
front to slide up near our southern border by the end of the day as
a sfc low near the MT/WY/SD border and pushes at least mid level and
high clouds across the area.

.LONG TERM...(Monday Evening through Sunday)
Issued at 315 PM CDT Sun Apr 16 2017

When the period opens Monday night, a low pressure system is moving
across the forecast area. Good precipitation chances exist with this
system, especially across north central and northeast South Dakota.
The forecast calls for a round of showers and thunderstorms Monday
night through Tuesday morning. The upper level flow pattern sets
up into an almost zonal pattern briefly before another low
pressure system moves out across the plains states mid-week.
Models are still in a fair amount of agreement with spreading
light to moderate rain/rain showers over at least the southern
two-thirds of the forecast area late Tuesday night through
Wednesday. Beyond that, there is some disagreement about how
shortwave energy within the flow pattern is handled Wednesday
night into Thursday. There continues to be pops/wx mentioned in
the forecast, though, from late Tuesday night through late
Wednesday night before pops diminish on Thursday. Models are all
consistent in creating a split in the upper level flow pattern on
Thursday, whereby this CWA ends up underneath very little in the
way of upper level steering flow. As a result much of Thursday
night through Saturday night should be a period of dry and
relatively calm conditions. By the end of the weekend, models
point to an end in the split flow pattern, potentially dragging
another area of low pressure southeastward across Montana, Wyoming
and the Dakotas.


.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1225 AM CDT Mon Apr 17 2017

VFR conditions are expected at all sites through Monday afternoon.
Showers and thunderstorms will develop across central SD Monday
evening and move east overnight. Cigs and vsby may fall in heavier
showers after 03z.




AVIATION...Parkin is the U.S. government's official web portal to all federal, state and local government web resources and services.