####018014139#### FXUS61 KCLE 241120 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 720 AM EDT Wed Apr 24 2024 .SYNOPSIS... Low pressure departing across Quebec will pull a trailing cold front southeast across the area this morning. High pressure over Ontario will build over the area by Wednesday night and continue to influence the weather through Friday before drifting east off the New England coast. A warm front will lift across the local area Friday night into Saturday. && .NEAR TERM /THROUGH THURSDAY/... At 7 AM the cold front extended from eastern Lake Erie to Cleveland to Findlay and will continue to move southeast. Showers are still ongoing ahead of the front and temperatures will begin to fall as the front moves through. The forecast remains on track with clouds filling back in. Previous discussion... The surface analysis early this morning shows the cold front is just approaching Lake Erie with an abrupt wind shift to the northwest behind it. The front will cross Lake Erie this morning but cold advection will continue to increase into this afternoon as temperatures at 925mb cool by 7-10C. Northerly winds will be breezy behind the cold front with winds gusting to around 20 mph at times. High temperatures will occur this morning ahead of the front with temperatures settling into the low to mid 40s this afternoon under mostly cloudy skies. When you take the wind into effect, wind chills will be in the mid 30s from North Central Ohio into Northwest Pennsylvania making for a chilly late April day. Showers continue to spread east across Lake Erie and eastern portions of the forecast area ahead of a shortwave and cold pool aloft. While the deeper moisture and better coverage of showers shifts east through 10 AM, scattered showers remain possible off eastern Lake Erie with lingering low level convergence before the ridge starts to build in this afternoon. Not quite cold enough for pure lake effect rain showers but some enhancement with scattered showers off the lake is expected. Moisture depth really decreases through the afternoon and expect the last of the light showers or sprinkles to be done by this evening. Have slowed down the clearing a little more with some breaks starting to develop downwind of the lake in NW Ohio by mid afternoon, then gradually scattering out through midnight as subsidence associated with the building high pressure wins out. With that said, some patches of cloud could remain tonight and complicate where Freeze Warnings/Frost Advisories may be needed. Decided to let the day shift monitor moisture and clearing trends and make the final call today. The forecast still supports a widespread freeze with much of the area dropping below 30 degrees and potentially a hard freeze with cooler spots into the mid to upper 20s. Winds will also be light which is conducive to widespread frost. Thursday will be mostly sunny, although a shallow cu field may develop inland from Lake Erie. With a continued cool northeast flow off the lake, lakeshore areas will remain near 50 degrees while southern areas should warm into the mid 50s. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... High pressure will be departing to the east Thursday night into Friday, though will still be close enough Thursday night to allow for one more mostly clear night with fairly light winds. There will be a bit more of a gradient than tonight and the airmass will be starting to warm a bit, so not expecting quite as much of a frost / freeze threat. However, with lows mainly ranging from the mid 30s to near 40 (locally near freezing from interior Northeast OH into interior Northwest PA) there should be some frost, though on a somewhat patchier basis than what's expected where skies clear tonight. Frost will favor locations away from the immediate lakeshore where winds are able to decouple. Much of Friday will be dry, though mid and high-level clouds will be on the increase with some potential for showers ahead of a warm front to approach I-75 by the early evening hours. Highs on Friday will respond nicely to the southeasterly flow and 850mb temperatures warming to 8-10C...most of the area should get into the low to mid 70s. Low pressure will develop over the Plains Thursday night into Friday and lift through the upper Midwest and Great Lakes Friday night and Saturday. This low will lift a warm front across the area Friday night into Saturday morning. As mentioned above, modest shower chances may begin encroaching on I-75 before sunset Friday, though otherwise activity will hold off until Friday night into Saturday morning from west to east. This won't be a big rain maker and with very modest amounts of elevated instability, severe weather isn't a concern either. However, a combination of the lifting warm front, support from the right-entrance quadrant of an upper-level jet streak Friday night into early Saturday, a fairly strong and moist low-level jet ascending into the upper-level jet support, and a flat mid-level shortwave supports most of the area seeing at least some measurable rain Friday night into Saturday morning. Given models are generally consistent on timing, maintain a period of likely to categorical POPs (60-80%) for nearly all of forecast area Friday night or early Saturday, save for the Mount Vernon area where POPs decrease into the chance (~50%) range. Have a slight chance of thunder mentioned as that's generally a good practice with warm fronts in the spring, but the amount of instability to work with will be limited so it should be more "showers" than "thunderstorms". Rain potential will diminish west of I-77 by early Saturday morning and will exit east of there by midday as the warm front and accompanying jet support continue lifting away from the area. This will leave a mainly dry Saturday behind the warm front, with just low chances for a stray shower or thunderstorm to pop up in the afternoon as weak instability tries developing. With some continued warm air/moisture advection continuing off and on through Saturday night keep some very low (20-30%) POPs in the forecast, especially over Northeast OH and Northwest PA...however, the forcing will be weak and instability limited, so still suspect that the general flavor for Saturday and Saturday night will be mainly dry once the warm front and associated showers are able to exit the area. Lows Friday night will range significantly from the mid 40s east of Meadville to the upper 50s to near 60 west of I-77 in Ohio. Fairly deep mixing into strong deep-layer southwest flow, the strong late April sun, and 850mb temperatures climbing to 12-14C will support highs ranging from the mid 70s to near 80 Saturday...perhaps a bit cooler in Northwest PA if clouds/showers linger longer. Lows Saturday night will be very mild, ranging from the mid to upper 50s in PA to the low to mid 60s across much of Ohio. It will be breezy to windy on Saturday, especially from mid-morning through early afternoon as the combination of a weakening (but still 40-45 knot) low-level jet and deepening mixing allows stronger gusts to mix down. Generally think much of the area will see 30-35 MPH gusts, though locations along the eastern lakeshore and generally northwest of I-71 may see a few hours of 40-45 MPH gusts. This is reflected by the NBM depicting modest probabilities (generally 20-40%) of gusts actually exceeding advisory-criteria (46 MPH) in a small chunk of Northwest and North Central OH. Ultimately do not think we'll need a headline anywhere but the wind will be noticeable on Saturday. && .LONG TERM /SUNDAY THROUGH TUESDAY/... A stout ridge will be in place over the eastern US Sunday and into Monday, with the ridge beginning to shift east and flatten later Monday into Monday night as a trough and associated cold front progress east out of the central US. Expect warm and mainly dry conditions (save for an isolated shower or storm) Sunday through a good portion of Monday. At some point late Monday or Monday night, expect greater rain chances to arrive along or just ahead of the advancing cold front. Models disagree somewhat on the frontal timing, with the GFS and Euro suggesting a passage Monday night into early Tuesday while the Canadian model is more solidly during the day Tuesday. If anything, timing has trended slightly slower in recent runs, which isn't unreasonable given the approaching trough will be flattening out as it approaches with a stout ridge only slowly giving way to the east ahead of the trough and cold front. Regardless, all models have a sufficient combination of moisture, modest instability, and forcing with the cold front and upper-level diffluence ahead of the approaching trough to suggest that much of the area should get wet with the cold frontal passage. Felt model agreement on timing was enough to hit everyone with at least one period of likely (60%) POPs at some point between late Monday and early Tuesday. POPs diminish west to east into Tuesday as high pressure will build in behind the front, though given some disagreement on the front's timing do hold onto at least a bit of a rain mention Tuesday east of a Sandusky to Upper Sandusky line. Temperatures will remain well above normal for Sunday and Monday, quite possibly approaching or reaching the low 80s across parts of the area, before cooling at least somewhat behind the front on Tuesday. Not looking at much of a severe weather or heavy rain threat with this front. Some models have a moderate amount of shear with enough instability late Monday into Monday evening that there could be a few stronger storms if frontal timing isn't too slow from the west, though overall am only seeing the ingredients in place for a rather low-end / run-of-the-mill severe threat, if even that. && .AVIATION /12Z Wednesday THROUGH Sunday/... At 11Z, a cold front extends from eastern Lake Erie to Cleveland to Findlay and will continue to move southeast through the rest of the area through 15Z. Showers are still ongoing ahead of the front and will taper off across far NE Ohio and NW Pennsylvania through early afternoon. MVFR clouds are filling in across the area and will persist through the afternoon. Patches of IFR are possible behind the front but are not expected to be widespread and will generally only last a couple hours at any point. Clouds will scatter out from north to south between 22-06Z. Southwest to west winds ahead of the front will shift to the northwest and eventually north for most of the day. Winds may occasionally gust to around 20 knots, at TOL/FDY/CLE during the late morning/afternoon on Wednesday. Outlook...Non-VFR may return in showers and thunderstorms Friday afternoon through Saturday. && .MARINE... Another day, another Small Craft Advisory for most of the nearshore waters between the Islands and Conneaut, OH as north-northwest winds freshen to 15-25 knots behind a cold front this morning. This will build 3 to occasionally 6 foot waves between the Islands and Conneaut. Winds and waves will be a bit weaker and smaller farther west towards Toledo and east of Conneaut, so did not include nearshore waters off of Lucas County OH or Erie County PA in the advisory. The headline runs 8 AM to 8 PM today, with some potential to be canceled a couple hours early if winds and waves can come down quickly enough later this afternoon. High pressure will move over the lake tonight before departing to the east/southeast Thursday into Friday. Tranquil marine conditions are expected tonight and Thursday morning. A period of 10-15 knot east-northeast winds may be just enough to build some chop between the Islands and Willowick, OH Thursday afternoon and evening. Otherwise, winds will remain east-northeast through Friday afternoon before shifting more south-southeast Friday night and southwest Saturday through Monday. Speeds of around 15 knots will be common Friday into Friday evening, which will build waves across the western and central basins...though the current wind/wave forecast does remain below Small Craft Advisory criteria for that period. The strongest winds are expected late Friday night into Saturday, as winds turn south and southwest at 20 to 25 knots. This will build 4 to 7 footers in the open waters, especially across the central basin, and will likely necessitate a period of wind-driven Small Craft Advisories for most or all nearshore zones late Friday night through a good chunk of Saturday. Strong offshore flow and cold waters could catch inexperienced mariners in smaller craft off guard, so don't want to downplay the potential need for advisories even with a purely offshore wind. Winds diminish into a 15-20 knot range for Sunday and Monday, which is still somewhat brisk but will allow marine conditions to improve somewhat. There is a low risk for isolated thunderstorms over the lake from Friday night through Monday afternoon. There is greater potential for thunderstorms over the lake Monday evening and night. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Freeze Watch from late tonight through Thursday morning for OHZ003-006>014-017>023-027>033-036>038-047-089. PA...Freeze Watch from late tonight through Thursday morning for PAZ001>003. NY...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LEZ143>148. && $$ SYNOPSIS...KEC NEAR TERM...KEC SHORT TERM...Sullivan LONG TERM...Sullivan AVIATION...KEC MARINE...Sullivan ####018004576#### FXUS63 KMQT 241121 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 721 AM EDT Wed Apr 24 2024 .KEY MESSAGES... - Cool and dry air, clear skies, and light winds today. - More unsettled weather expected for the coming weekend. && .SHORT TERM /THROUGH THIS AFTERNOON/... Issued at 424 AM EDT Wed Apr 24 2024 GOES-16 Channel 10 Water Vapor imagery shows significantly drier air moving over the UP this morning. RAP Analysis shows 500mb height rises as ridging builds over the UP following the passage of the trough responsible for yesterday's active weather. Under northwesterly flow aloft, cooler temperatures prevail today with NBM mean highs only in the mid 30s along Lake Superior and upper 40s further into the interior west. With clear skies, efficient mixing of dry air aloft is expected, with the 10th percentile of all available model guidance over the UP suggesting dew points nearing the single digits, resulting in RH values in the 20s and upper teens in the interior of the UP. While normally this would be a concern for fire weather, the ridging will provide light and variable winds of 5-10 mph. Given those winds and the cooler temperatures and recent precipitation, fire weather concerns are lower than previous dry weather days. CAMs do indicate some lake breeze activity today, particularly from Lake Michigan and along the Keweenaw. && .LONG TERM /TONIGHT THROUGH TUESDAY/... Issued at 312 AM EDT Wed Apr 24 2024 Upper air pattern consists of a trough on the west coast, a ridge in the plains and a trough on the east coast 00z Thu. Troughing moves into the central Rockies 00z Fri with a ridge over the upper Great Lakes. The trough then becomes negatively tilted in the central plains 12z Fri and then moves into the upper Great Lakes 12z Sat. Deeper moisture and 850-500 mb q-vector convergence moves into the area 18z Fri and remains into 12z Sat. Did slow down pops into the area Friday as they looked way too fast with a system being negatively tilted and antecedent airmass out ahead of it is awfully dry. Went dry for Fri morning and would not be surprised if Fri for the whole area does not turn out to be dry. In the extended, the GFS and ECMWF show a 500 mb trough in the southern Rockies and a negatively tilted shortwave over the upper Mississippi River Valley and a ridge on the east coast 12z Sat. The trough moves into the central plains 12z Sun and then becomes negatively tilted as it moves northeast into the upper Great Lakes 12z Mon. This negatively tilted trough slows down and remains over the upper Great Lakes 12z Tue. Ridging then moves into the area 12z Wed. Temperatures are above normal on Saturday and then fall to near normal Sunday into Tuesday with an active and wet weather pattern setting up. Temperatures go back above normal on Wed. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 721 AM EDT Wed Apr 24 2024 Barring the unlikely persistence of a borderline SCT/BKN MVFR cloud deck above SAW, a high pressure over northern Ontario will keep clear VFR conditions through the entire TAF and too dry of conditions for any fog. Northerly and northeasterly winds will turn easterly and eventually southerly tonight but will remain mainly light and under 8 knots. && .MARINE... Issued at 312 AM EDT Wed Apr 24 2024 Winds continue to diminish below 20 knots today as high pressure builds in. This high then lingers over the Great Lakes through Thursday which will keep winds suppressed until Friday when winds will increase from the southeast/east to 20 to 30 knots and may push gale force gusts up to 40 knots Friday night along the U.S. Canadian waters region of eastern Lake Superior. Low pressure then forecast to track northeast across the region this weekend...which in turn will bring winds back around from the north in the Sunday time frame. Winds stay up to around 30 knots Saturday into Monday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Small Craft Advisory until noon EDT /11 AM CDT/ today for LSZ240>245-251. Small Craft Advisory until 2 PM EDT this afternoon for LSZ248>250. Lake Michigan... Small Craft Advisory until 8 AM EDT this morning for LMZ221- 248-250. && $$ SHORT TERM...GS LONG TERM...07 AVIATION...GS MARINE...07 ####018005178#### FXUS63 KARX 241124 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 624 AM CDT Wed Apr 24 2024 .KEY MESSAGES... - Sunny and dry today with freezing temps tonight east of the Mississippi River - Dry air and gusty conditions Thursday will lead to elevated fire wx concerns, especially east of the Mississippi - Active pattern to finish the week with multiple days of rain and thunderstorms chances Friday through the weekend. && .DISCUSSION... Issued at 317 AM CDT Wed Apr 24 2024 Today through Thursday: Sunny and Dry, Elevated Fire Weather Concerns Thursday High pressure across Ontario sinks south into the Great Lakes region today, bringing ample sunshine and clear skies across the region. As typical with Canadian high pressure systems, dry air will move in across the region, bringing RH values into the low to mid 20 percent range. So while there is some fire weather risk associated with these temps and RH values before we fully green up, we will also see winds below 10 mph this afternoon, which should limit the risk. High pressure shifts to the eastern Great Lakes overnight tonight with clear skies expected. Winds do increase slightly overnight from west to east late, but there is a good chance for sub-freezing temps east of the Mississippi. The chances increase further into the region of high pressure to the north and east. Neighbors to the east will host a Freeze Watch for tonight, but we will hold off for now given the lower chances (10 to 30% of sub freezing temps) where we are currently issuing frost/freeze headlines (Grant, Crawford, Richland, and Vernon). We will lie between an exiting high pressure to the east and a developing low pressure across the Rockies. With the dry airmass from the high pressure system still influencing our area, RH values will still fall into the low to mid 20s east of the river and around 30% west of the river. Southeasterly winds will increase into the 15 to 25 mph range across the region, which when combined with the lower RH values, will lead to elevated fire wx conditions. Friday into the Weekend: Active Pattern with Multiple Days of Rain and Thunderstorms A pattern shift will take hold across the CONUS Thursday night into Friday as upper-level ridging gives way to a negatively-tilted trough and an associated low pressure system lifting NE from the Central Plains into the Great Lakes Friday into Friday night. This wave will bring the first higher chances of rain and stronger thunderstorms across the area, with another round likely again on Sunday following a very similar track as the low on Friday. Strong moisture advection will take place Thursday night into Friday as PWATs increase from roughly 0.3 inches Thursday to 1.3 inches Friday. There is widespread lift moving into the region on Friday that will support widespread showers and thunderstorms by Friday afternoon; however, models are favoring the surface warm front and associated severe weather risk to be predominately south of us. SPC does have our local area in a marginal risk at this time, so something to keep an eye on over the next day or so. A strong LLJ Friday night into Saturday could bring a stronger storm or two northward into our area, but there is uncertainty on that due to earlier convective contamination. There will be a slight lull in precipitation across the local area on Saturday, but another leeside low pressure system will be developing across the Central Plains. This low advances northward Sunday into the local area, with better thermodynamics across our area on Sunday than models suggest Friday. Better shear on Sunday appears to be to the east and south of our local area, but still expecting showers and thunderstorms to be prevalent across the area. Will continue to monitor the threat of severe storms across our local area. Multiple days of precipitation will bring rainfall amounts around 1.5 to 2.5 inches, but NBM probs suggest a 10 to 20% chance for a 3 inch total across 72 hours Friday into Sunday. For 2 inches, NBM probs are around 50 to 70%. Latest HEFS (Hydrologic Ensemble) across the area shows the Kickapoo River has roughly a 10% chance of reaching or exceeding minor flood stage, while the downstream locations of the Turkey River (Elkader) has roughly a 10% chance of reaching minor flood stage and a 5% chance of reaching moderate flood stage. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 613 AM CDT Wed Apr 24 2024 Light northeast winds will transition to light southeast winds throughout the day. Mostly sunny skies expected today with some mid level clouds entering the area this evening. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...Freeze Warning until 8 AM CDT this morning for WIZ032-033. MN...Freeze Warning until 8 AM CDT this morning for MNZ079-086>088- 094>096. IA...None. && $$ DISCUSSION...JAW AVIATION...Cecava