679 FXUS63 KDTX 232310 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 610 PM EST Tue Jan 23 2018 .AVIATION... Remnant light snow/freezing drizzle will end around PTK and DET by 00Z as a sfc cold front and mid level moisture exit to the east of the region. Regional satellite/sfc obs show ample stratus blanketing lower Mi. A deepening low level inversion and lingering low level cyclonic flow will hold stratus in place across Se Mi through at least daybreak Wed. Ongoing low level cold air advection will result in a subtle rise in the inversion heights. This should result in a subtle trend toward cigs rising into the 2-3k ft range late this evening into the overnight. For DTW...Ceilings look to fluctuate above and below 2k feet for at least the next couple of hours. There are higher probabilities for cigs to be above 2k ft overnight. The onset of nighttime cooling and weakening sfc gradient will result in a slow decrease in the westerly winds during the night, with a direction shift toward 290 to 300 degrees expected between 01Z and 02Z. /DTW THRESHOLD PROBABILITIES... * High for ceilings less than 5000 ft tonight and Wed morning. Moderate Wed afternoon. && .PREV DISCUSSION... Issued at 338 PM EST Tue Jan 23 2018 DISCUSSION... Surface trough transiting the CWA is supporting light snow showers this afternoon leading to nothing more than minor accums. Coverage and intensity will continue to decrease as large scale forcing and better moisture strips east. Cold advection within gusty northwest wind will continue through the night as 850mb temps fall from around -8C at press time to -13C Wednesday morning. Temps in the mid to upper 20s over Wisconsin and northern Lower support going forecast lows in the upper teens and low 20s, except the far south CWA where cold fropa has yet to occur this aftn and arrival of coldest air will be delayed. Some potential for lower temps across the north as trailing dry advection, which is already advancing the back edge of lake clouds over Lake Superior, works into the area from the NW and potentially clears out low cloud as the gradient slackens post 06z. A run to the low teens is not out of the question in the Thumb, but remained conservative given uncertainties and lack of snowcover. Thermal trough directly overhead to start Wednesday will ensure a low ceiling on temps. Subsidence beneath incoming upper ridge will reinforce existing inversion, supporting a more pessimistic cloud forecast overall for Wednesday, especially considering mid/high clouds streaming associated with the trough over the northern Great Plains will be streaming overhead. No qualms with a mid to upper 20s forecast for highs, keeping in mind some underachieving potential will exist conditional on opacity/coverage of boundary layer clouds. Confluent upper flow in advance of upper ridging will force surface high pressure across the area early Thursday, scouring any remaining low clouds before emerging return flow signals the arrival of a shallow warm front likely to cause low clouds to return for at least part of the day Thurs and a modest recovery in temps of about +5 over Wednesday's values. An upper level ridge axis crossing the region on Friday and low pressure moving eastward through central Ontario will bring increasing southwesterly flow through the day allowing highs to approach 50 under mostly sunny skies. The low pressure will then pull a cold front slowly eastward across Lower Michigan on Saturday. Increasing moisture transport ahead of the front will bring rain shower chances late Friday that will continue throughout Saturday as temperatures remain well above average in the upper 30s to mid 40s. Model solutions continue to differ on the exact details of frontal timing and where the greatest moisture transport will take place ahead of the front. The GFS keeps the bulk of moisture east of SE Michigan on Saturday while the Euro and CMC pull moisture directly over SE Michigan late Saturday. After the frontal passage, temperatures will fall slightly into the 30s on Sunday before a secondary cold front brings a stronger push of cold air to the region late Sunday into Monday. A chance for snow showers will accompany the second frontal passage as temperatures return closer to average with highs in the low 30s and lows in the upper 10s by Monday. MARINE... Low pressure centered over central Lake Huron this morning will lift northeast into Ontario during the daylight period. Moderate northerly winds currently residing north of this low over the north half of lake Huron will expand across the entire lake Huron basin as the low exits. This will be accompanied by colder air, which may lead to a brief period of gusts to near gales late this afternoon through early tonight. Winds and gusts will decrease Wednesday as weak high pressure lifts across the region. Relatively light winds will remain in place through the end of the week. Another increase in winds will come for the weekend. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...Gale Warning until 10 PM EST this evening for LHZ362-363. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && $$ AVIATION.....SC DISCUSSION...JVC/JD MARINE.......DG You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.