084 
FXUS63 KFGF 050359
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1059 PM CDT Thu Apr 4 2019

.UPDATE...
Issued at 1009 PM CDT Thu Apr 4 2019

Surface observations show reduced visibilities remaining mainly 
in the 3 to 5 mile range throughout eastern ND and west of the 
immediate RRV, and guidance suggests that widespread fog 
development, if it occurs, would hold off until the early morning 
hours. Thus will continue to monitor for additional development. Of
additional interest is an area of isolated showers and 
thunderstorms that have advected into the Devils Lake basin late 
this evening. SPC mesoanalysis indicates an area of weak MUCAPE 
that could allow for this activity to persist for another few 
hours, progressing into the central valley.

UPDATE Issued at 706 PM CDT Thu Apr 4 2019

Main impact overnight will be areas of fog development. As strong
mid to low level warm air advection develops ahead of the 
approaching front, a strong low level inversion develops with a
saturated boundary layer. Visibilities have begun to reduce over 
portions of northeast North Dakota already, and high resolution 
models suggest coverage of reduced visibilities to continue to
increase overnight and into the early morning. There is still 
some uncertainty in the extent of coverage so will monitor 
coverage of fog development throughout the evening.

&&

.SHORT TERM...(This evening through Friday night)
Issued at 338 PM CDT Thu Apr 4 2019

Shortwave trough actively transitioning over our CWA, while 
southerly low level flow has developed bringing weaker WAA to our 
CWA. Showers continue to transition eastward, and temps have held in 
the mid 30s in the north, with wintry mix mainly of rain/snow where 
precip tracks. Some snow grains or even sleet has mixed at times 
with some of the showers. Short range guidance has this almost 
completely ending over much of the area, but may linger in our far 
northeast through the night into Friday morning. Winds have 
increased with southerly flow, with gusts 30-35 mph and possibly a 
few 40 mph gusts before sunset. 

A cold front will drop south Friday and stall with WAA still 
expected near our southern CWA. Easterly flow north of this front 
may support fog development Friday morning (especially in areas of 
clearing). Lows tonight may still fall near or slightly below 
freezing for some, but many locations may remain above freezing. Low 
clouds may also linger north of this front Friday, and a large 
spread in temps may result in far north locations during the day 
near 40 and south of the front in the 50s. 

.LONG TERM...(Saturday morning through Thursday) 
Issued at 338 PM CDT Thu Apr 4 2019

Saturday-Sunday night: Trough moves out of the western US, with 
strong WAA and moisture advection advertised to overspread our CWA. 
Temperatures may fall near or slightly below freezing Saturday 
morning, but will remain mild and above freezing through Sunday 
night. Daytime highs still approaching 50 for manly locations and 
possibly 60s in our south. 

Regarding precip this weekend: There are still variances in the 
evolution of this pattern and where synoptic/mesoscale forcing line 
up, but there is a strong signal between all guidance that an 
anomalously moist air mass will be in place with PWATs around 1" by 
Saturday night and Sunday morning. Widespread light precip appears 
likely Saturday night and Sunday, but questions remain whether this 
could be a more impactful system from a rainfall perspective. During 
that period guidance is showing widespread precip potential and NAM 
especially is showing potential for banding along 700MB deformation 
axis. Instability may be in place as well and if  banding and 
thunderstorm activity were realized widespread moderate to locally 
heavy rainfall would be possible (0.5-1.0"). This signal is 
concerning, but confidence is not high on occurrence, coverage, or 
location at this time. This needs monitored closely. 

Monday-Thursday: Trend will be toward near normal to below normal 
temperatures with overnight lows below freezing. There may be a few 
light precip chances, but any stronger systems are shown by guidance 
to remain south of our region at this time.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 706 PM CDT Thu Apr 4 2019

Expect southerly winds to slowly weaken to 5 to 10 kts overnight.
Low VFR to low MVFR ceilings will prevail early this evening, 
then deteriorate overnight to IFR and LIFR as fog spreads in 
along and north of Highway 200 impacting DVL, GFK, TVF, and BJI, 
as well as areas north. Potential exists for fog development for 
areas south, including FAR, but coverage is expected to be less. 
IFR/LIFR fog is most likely from 10z to 15z, with conditions 
slowly improving late in the morning.


&&

.HYDROLOGY...
Issued at 1100 PM CDT Thu Apr 4 2019

Snowmelt continues to facilitate increasing water levels across 
much of the southern and central Red River Basin. After a below 
freezing Friday night, an increase in snowmelt will trend 
northward this weekend as temperatures are expected to remain 
above freezing across the region on both Saturday and Sunday with 
widespread 40s and 50s for daytime highs. 

The southern portions of the Red River Valley including Hickson, 
Lisbon, Hawley, and Mapleton, are seeing water levels gradually 
level off; however, they are expected to remain in flood stage for 
the next few days. Wahpeton, Sabin, and Dilworth will see gradual 
decreases in water levels.

All other forecast points within the Red River Valley basin are 
showing rising water levels. Flood warnings have been updated or 
issued for East Grand Forks, Shelly, Climax, Twin Valley, and 
Crookston as river levels are expected to increase well into flood 
stage within the next 7 days. Major flooding is still expected at 
Fargo and is now expected in Grand Forks. 

Ice jams remain a concern heading into the late week/weekend. Recent 
satellite imagery shows considerable river ice remains in the 
northern half of the mainstem Red River as well as many smaller 
tributaries. Locations that are prone to ice jam flooding, such as 
Oslo and Crookston, should monitor water levels closely in the 
coming days as ice debris slowly make their way through local 
waterways. 

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

Areal and river point flood warnings continue across portions of
the region. Refer to the latest flood warnings and statements for
detailed information on specific locations.

&&
$$

UPDATE...BP
SHORT TERM...DJR
LONG TERM...DJR
AVIATION...BP
HYDROLOGY...Lynch