413 FXUS63 KFGF 011757 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1257 PM CDT Sun Sep 1 2019 .UPDATE... Issued at 1254 PM CDT Sun Sep 1 2019 Area of clearing has been expanding in our west, with a second "hole" opening over north central SD that is showing signs of clearing. These areas may fill back in with CU during peak heating, but this could be a good sign for potential for highs to get to upper 70s if those areas remain mostly sunny/partly cloudy in cloud coverage. Adjustments made to sky cover and minor adjustments to temps to match current trends. UPDATE Issued at 1018 AM CDT Sun Sep 1 2019 Persistent low cloud cover with only a few breaks between DVL and GFK may throw a wrench into our temp forecast today if they are slow to clear as latest short range/high res guidance indicates. Associated with the stratus are some pockets of drizzle (not being samples by radar), while actually measurable isolated- scattered showers are still near the International Border. Adjustments made to PoPs/Sky to reflect current trends, and I nudged down high temps (still not as low as "coolest LAV guidance). UPDATE Issued at 632 AM CDT Sun Sep 1 2019 Forecast on track with a few showers hugging the Canadian side of the International border. A gradual slide southward is still expected as the day goes on. Also seeing some light returns in west central MN sliding to the east in the moist WAA 850 to 700mb layer. && .SHORT TERM...(Today and tonight) Issued at 404 AM CDT Sun Sep 1 2019 Concerns for today will be temps as cloud cover lingers into the afternoon and shower chances. Scattered showers along the northern border will slide south and east along a weak boundary this morning. Depending on amount of clouds and sun some instability will develop, MUCAPE in the latest run of HRRR brings up to 1000J/kg along the boundary this afternoon, showers will continue to develop into the afternoon and may get some embedded thunder. Coverage is expected to be isolated at best along the boundary given the low instability and will diminish this evening. Afternoon highs will depend on cloud cover with a range of solns given in the guidance this morning. Mid 70s where clearing takes place and mid 60s where clouds persist. NW MN should see clouds persist and SE ND has the best chance of seeing the warmer temps. .LONG TERM...(Monday through Saturday) Issued at 404 AM CDT Sun Sep 1 2019 The severe storm risk remains for the northern plains as upper wave and attendant SFC low organize across the high plains Monday. Models in fair agreement with some elevated showers on WAA wing will work into the Devils Lake basin before noon. By the mid afternoon storm initiation could occur across central ND along weak SFC low with convection spreading to the east southeast. With shear profiles storms will initially be supercells and then transition to more of a wind threat. The amount of SFC based instability will define the tornado threat with uncertainties surrounding cloud cover and moisture return across eastern ND either allowing the tornado threat to grow or limiting the threat and thus the event would be more of a wind threat. There is guidance and potential for a significant wind event with gusts to 75mph over an extended area. If this initial activity does not form from lack of instability then convection will be delayed a few hours until parent SFC low and cold front push southeast from Canada. Nonetheless widespread rainfall is expected by Monday evening into the overnight with amounts set to range in the southern valley from near a third of an inch to near 1.5" in northwest MN. Upper low slides eastward Tuesday, facilitating strong northwest flow both aloft and at the surface in association with relatively sharp pressure rises. Sustained winds will be around 20 to 25 knots, especially for the James Valley region, with gusts of 30 to 35 mph. Scattered showers will continue moving out of our eastern most counties by midday. A weak H5/H7 shortwave traverses the region Wednesday afternoon, during which time we could see brief wind shifts and a slight chance for showers east of the Red River along the International Border. The reprieve from northwest flow will be enough to allow temperatures to rise into the 70s as a shortwave ridge quickly passes through the region Thursday afternoon. This warmer weather will be short lived as a rather strong upper low dives out of northern Manitoba into Ontario, bringing a cold front through the region early Friday morning. Due to an abundance of dry air in place, the frontal passage is expected to be dry. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 1254 PM CDT Sun Sep 1 2019 Areas of MVFR stratus eroding west to east, though early in the TAF period pockets of 1500-3000 KFT AGL ceilings will remain possible in eastern ND before VFR is favored. Northwest MN is much less certain as it remain well within area of IFR to MVFR ceilings and it may take longer for this to erode. There is some indication that MVFR ceilings prevail through the end of the TAF period at KBJI where fog may also develop 10-15Z period (held off on vis restrictions). A few showers are moving north of Highway 2 early this afternoon and additional showers or drizzle can't be ruled out elsewhere, though confidence not high enough to introduce at this issuance. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...DJR SHORT TERM...JK LONG TERM...JK/Lynch AVIATION...DJR