National Weather Service Raw Text Product
Displaying AFOS PIL: AFDGRR Received: 2018-11-20 11:18 UTC
639 FXUS63 KGRR 201118 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 618 AM EST Tue Nov 20 2018 LATEST UPDATE... Aviation .SYNOPSIS... Issued at 230 AM EST Tue Nov 20 2018 Light snow showers and flurries will taper off early this morning. Another clipper system will bring light snow showers again tonight. High pressure will bring fair but continued cold weather Wednesday through Thursday before temperatures undergo a moderating trend Friday through the weekend with a chance for rain showers this weekend. && .DISCUSSION...(Today through next Monday) Issued at 230 AM EST Tue Nov 20 2018 A few light snow showers and flurries will linger over our southern fcst area for 2-3 more hours (mainly south of I-96) early this morning before weak ridging briefly builds in to bring tranquil wx today. However another clipper system will move in from the northwest tonight and bring another round of light snow showers. A consensus of latest high res guidance continues to suggest that light accumulations of less than an inch will occur tonight. The relatively higher amounts of over a half an inch are most likely to occur near to west of US-131 due to lake enhancement with little to no accumulations over our eastern fcst area. High pressure building southeast from Canada will bring fair but cold wx Wednesday through Thursday. Temperatures will undergo a gradual moderating trend beginning Friday as strong southerly flow warm air advection develops on the back side of the departing ridge. Persistent southerly flow will also result in an increase in moisture and some showers are forecast this weekend. A potentially stronger low pressure system is likely to move across the lower Great Lakes region late Sunday into Monday bringing potential for more widespread rain. A colder airmass will advect in behind that system early next week and cause pcpn to change over to snow showers by late Monday/Tuesday. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 615 AM EST Tue Nov 20 2018 Light snow showers will be around for part of today leading to local impacts. Tonight a more widespread area of snow showers is forecasted to move in. Confidence is high that we will see MVFR conditions along with an increased risk for local IFR and lower conditions. Gusty winds are expected tonight with some values over 20 knots near the lakeshore. && .MARINE... Issued at 230 AM EST Tue Nov 20 2018 Wave heights will remain hazardous to small craft this morning before subsiding a bit briefly this afternoon. However winds and waves will ramp back up tonight after the passage of another cold front. Southwest winds to 20 to 30 kts are anticipated this evening which will veer to the northwest overnight and remain up around 20-30 kts after frontal passage. && .HYDROLOGY... Issued at 217 PM EST Mon Nov 19 2018 There are no hydrologic concerns through the end of the week. A few rounds of light precipitation, mostly falling in the form of snow, will affect the area through Wednesday. The first will be this afternoon through tonight, with a few light showers lingering near the lakeshore through early Tuesday. The second round will occur Tuesday night into Wednesday morning. Thursday and most of Friday look dry. Longer range models then continue to show a wetter pattern setting up Friday evening through early next week. Several rounds of rainfall look to occur, although the timing from Saturday onward is still uncertain as forecast models vary widely with the timing, track, and strength of low pressure systems near the region. We will continue to monitor potential rainfall amounts, but it does not look like there will be flooding concerns. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...Small Craft Advisory until 5 PM EST Wednesday for LMZ844>849. && $$ SYNOPSIS...Laurens DISCUSSION...Laurens AVIATION...MJS HYDROLOGY...HLO MARINE...Laurens