Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 KFGF 191753

Area Forecast Discussion
National Weather Service Grand Forks ND
1253 PM CDT Tue Sep 19 2017

Issued at 1253 PM CDT Tue Sep 19 2017

Tweaked timing of precip a bit. There have been some clearing
spots starting to develop over the CWA. Temps have already reached
the lower 70s in the south and 60s in the north even with cloud
cover, so will keep temps on track to top out in the upper 60s
north to near 80 south. Even with spotty clearing across the
region the forcing from the upper system still will be enough to
generate severe weather under a high shear/low CAPE scenario. At
this point damaging winds seem to be the primary threat.


.SHORT TERM...(Today through Thursday night)
Issued at 353 AM CDT Tue Sep 19 2017

Upper level trough over the Pacific Northwest with an upper level
jet around the south and east sides of the trough will shift east
today. Height fall better than 100M will move into the forecast
area after sunset Wed. Stronger upper level jet will round the
base of the trough and into the area after 06z Wed. Model soundings
indicate an inversion until mid-late afternoon. Severe weather is
expected from mid afternoon into the evening. Good shear profiles
and decent amount of instability is forecast for the
afternoon/evening along with the dynamics.

Fog loop indicated low clouds covered the forecast area this
morning Low clouds should dissipate mainly in the southern
zones by late morning/early afternoon.

.LONG TERM...(Friday through Monday)
Issued at 353 AM CDT Tue Sep 19 2017

Most of the Friday to Monday time frame continues to feature south
to southwest flow at 500mb. At the surface, a persistent boundary
will set up from southwest to northeast through the FA. Because the
500mb flow is more south-southwest than true southwest, this surface
boundary will not move eastward very much each day. Therefore,
periodic waves of energy are expected to ride up the 500mb flow and
interact with the surface boundary and produce a pretty wet period.
The entire four days may not wet, as some brief dry periods will
also mix in, but it will generally be wet. With the surface boundary
moving a little eastward each day, the Devils Lake region may get
out of the wet pattern a little earlier than other areas. With a
steady amount of cloud cover expected with the rain, temperatures
will generally stay on the cooler side.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1253 PM CDT Tue Sep 19 2017

Some MVFR to IFR ceilings continue over the northern and western
TAF sites, but there has been some clearing developing just east
of the Red River. There will be a line of thunderstorms moving
into the region this afternoon and evening, with storms most
likely around KDVL in the 22-00Z time frame, moving into the
central TAF sites at 01-04Z, and later on for the MN sites. As
always, ceilings and visibility will be highly variable with
convection moving through, so there could be some brief drops to
MVFR to IFR with strong wind gusts above 30 kts as the cells move
through. Winds will shift to the west as the thunderstorms move
east, and there will be period of MVFR ceilings in some areas
behind the line but all sites should improve to VFR by the end of
the period.




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