Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/29/22

Area Forecast Discussion
National Weather Service La Crosse WI
1000 PM CDT Mon Mar 28 2022 .DISCUSSION...(This evening through Monday) Issued at 235 PM CDT Mon Mar 28 2022 Key Messages... - Calm weather for the rest of today through tomorrow. - A storm system will impact the area Tuesday night through Thursday. Freezing rain and ice accumulation is expected Tuesday night north of Interstate 94, which will impact the Wednesday morning commute. Otherwise, precipitation type will vary throughout the event between rain, snow, and a wintry mix. Some thunderstorms and gusty winds are also possible with this storm. Tonight and Tomorrow... Conditions will remain pretty tranquil through most of Tuesday as the large area of high pressure over the region today departs slowly off to the east/southeast. The main concern is how quickly some showers may start to break out Tuesday afternoon ahead of the incoming storm system from the southwest. Almost all the hi-res models are suggesting that all of Tuesday will be dry with the shower development occurring during the evening. However, the RAP has been showing some mid-level frontogenesis coming across in the afternoon along with some isentropic up glide and moisture transport into the area on the 290K surface. Based on this, will leave some small rain chances in the forecast for Tuesday afternoon, but it could end up being nothing more than some sprinkles. Tuesday Night to Thursday... Still looking at a spring system of mixed precipitation to impact the area mid-week. A low pressure system will push into the area Tuesday morning from the southwest, with the center of the low centered right over the area late Tuesday night/early Wednesday morning. GFS has the center of the low around 987 mb. As the closed low moves in, the pressure gradient will tighten, heightening wind speeds and increasing possible gust speeds. Most models have the system`s associated precipitation beginning to impact the area ahead of the low on late Tuesday afternoon or early Tuesday evening. This widespread precipitation will stick around until around Thursday night. Southwesterly moisture advection will provide a hefty moisture source for this precip. GFS/European models suggest about 0.8 to 1.1 inches of PWAT, with even higher amounts to the southeast. These values are well above the area`s median average (0.35 inches) for this time of year, according to the SPC Sounding Climatology page. EPS models generally agree on precip continuing throughout the day Wednesday, again with most members keeping the precip in the area until later Thursday. The more complicated part of this forecast lies in determining what kind of precipitation we can expect. Overall, expect a wintry mix of rain and snow, with some potential for freezing rain, especially in northern parts of the CWA in central Wisconsin. Mainly rain is expected Tuesday through Wednesday, with freezing rain in central Wisconsin. This should then transition to all snow Wednesday night as temperatures aloft dip and remain below freezing. A mix of rain and snow is then expected for Thursday and Thursday night, depending on the area`s temperatures aloft. This event, especially on Tuesday and Wednesday, is of the low CAPE/high shear variety. Model soundings show a skinny CAPE of 150-400 J/kg, particularly in NE Iowa, with 0-6 km wind shear of 80-90 kts in much of the area. Thunder is possible here, especially considering the stronger signal for storms just to the south in Iowa. SPC`s Day 2 outlook currently has a marginal just clipping a portion of NE Iowa in the CWA. Other areas in Minnesota and Wisconsin also have some CAPE signal, so thunder is possible there as well, as this could play out like a convective storm at times, including strong wind gusts. Total snow accumulation from this event is about 0.5-3 inches, with the higher amounts in SE Minnesota and western/central Wisconsin. Freezing rain in central Wisconsin will be the main threat to watch out for Tuesday night into Wednesday morning. NBM 4.1 models have signaled this outcome for several days now, though the threat has moved more northward during those runs. In more recent runs, temperature spread in central Wisconsin has decreased and centers right around 32 F. GEFS models have also continued this signal. Nearly all members of the WPC Super Ensemble suggest at least some accumulation of ice Tuesday night, with most members staying under 0.2 inches. Mean ice accumulation is about 0.11 inches. Higher accumulations closer to or above 0.2 inches are not out of the question, especially due to the convective nature of the event and CAPE values in the area of about 250-300 J/kg. However, warmer air should advect into the area Wednesday, warming surface temperatures above freezing, and mitigating at least some of the icing impacts in the afternoon. Due to the peak icing period being overnight, the morning commute is likely to be impacted by icy roads. A Winter Weather Advisory will likely be needed for this period. Unless the convective nature of the rain does take over, ice accumulations of 0.25 inches warranting an Ice Storm Warning look less likely, but will be something to keep an eye on as the event nears. Friday to Sunday... A bit calmer stretch of weather is expected over the weekend. Friday should be dry, then followed by light snow and light rain impacting the area Saturday. Highs will be in the mid 40s to mid 50s through the weekend. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1000 PM CDT Mon Mar 28 2022 Cigs: bkn high/mid level clouds through Tue morning will start to lower for the afternoon, with MVFR/IFR expected Tue evening. These low cigs will likely hold across the TAF sites through Wed night. WX/vsby: some hints in the models of weak isentropic upglide and a bit of elevated frontogenesis that will sweep northeast across the area Tue afternoon - potentially firing off some showers. Most meso models favor dry at this time while bufkit soundings also showing a robust dry sub cloud layer. Will keep shra out of the forecast for now. That said...widespread rain/showers is expected Tue night, with on and off pcpn continuing through Wed. A threat for isolated thunder Tue evening, with a swing to some snow Wed night into Thu. Expect vsby impacts. Winds: sfc pressure gradient tightening tonight and winds will be on the increase - especially by early Tue morning. Sustained around 20 kts for KRST, with gusts around 30. Should stay southeasterly through Tue night. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ DISCUSSION...Dahl/04 AVIATION.....Rieck
Area Forecast Discussion
National Weather Service Cleveland OH
941 PM EDT Mon Mar 28 2022 .SYNOPSIS... A deep trough over the eastern Great Lakes will shift east tonight and Tuesday as high pressure slides into the Ohio Valley. Strong low pressure developing in the Plains Tuesday night will push a warm front across northern Ohio and northwest Pennsylvania by Wednesday morning. This low will lift through the western and central Great Lakes Wednesday night and Thursday pulling a strong cold front through the region. && .NEAR TERM /THROUGH TUESDAY NIGHT/... Skies cleared out nicely as diurnal clouds and snow dissipated over the last few hours. Exception is the band of clouds and snow showers over northwest Pennsylvania at this time. Expecting this activity to wane with time as high pressure builds in from the west. Otherwise, clear skies elsewhere with diminishing winds. Temperatures look reasonable with good radiational cooling expected. Previous Discussion... Deep mid/upper troughing remains entrenched across the eastern CONUS this afternoon, but it is beginning to slowly shift east as broad upstream mid/upper ridging progresses through the Plains. Strong 1030 mb arctic high pressure moving into the western Great Lakes this afternoon is beginning to feed drier air into the backside of the mid/upper trough, so the lake-effect bands are finally beginning to weaken as anticyclonic flow and drier air take hold. Regional radar loops upstream show the connections to Lake Superior and Lake Huron continuing but showing signs of weakening. Nevertheless, expect widespread coverage of mainly nuisance snow showers to persist through the evening in most of northern Ohio and NW PA, with the greatest coverage in the highest peaks/favored upslope areas of the primary and secondary snowbelts in 330-340 degree flow. This is due to strong cold air advection of -18 C 850 mb temps over lake waters in the upper 30s F leading to lake induced CAPES of 400-600 J/kg, inversion levels hovering around 6-7 thousand feet, and equilibrium levels around 8-9 thousand feet. NAM and RAP BUFKIT soundings show moisture and lift in the DGZ decreasing this evening through tonight from west to east as the high builds in, so expect the activity to gradually end from west to east late this evening and early tonight. Kept chance PoPs from Ashtabula County east through Erie and Crawford Counties in PA through the night since moisture and inversion levels will take longer to decrease in that area, along with a Lake Huron fetch. In terms of accumulations, the bulk of that is over with just an additional trace to 0.5 inch over north central and NE Ohio (highest in the peaks of the primary and secondary snowbelts) and 1-2 inches in Ashtabula, Erie, and Crawford Counties through tonight. Winds will remain up in the 10-20 knot range with occasional gusts over 25 knots late this afternoon, but these will decrease to 5-10 knots by tonight. The clearing skies and decreasing winds will lead to a cold night, so used the colder CONSSHORT temps for lows which yields around 20 in most areas with mid/upper teens from NE Ohio through NW PA. On Tuesday, the aforementioned mid/upper ridge over the Plains will be forced east into the Midwest and western Great Lakes as a strong trough amplifies into the western CONUS. This will lead to rising heights across our region and the surface high becoming centered over the Ohio Valley. Mostly sunny skies much of the day and developing warm air advection aloft will boost highs into the low/mid 40s in most areas except mid/upper 30s in NW PA. This is still a solid 8 to 12 degrees below normal for late March, but it will certainly feel better after the unseasonably cold weekend. Moving into Tuesday night, the big trough out west will shift into the Plains with the left exit of a 120+ knot H3 jet streak rounding its base supporting strong surface cyclogenesis over the KS/MO/IA vicinity. This will push a strong warm front northward across our region late Tuesday night, with strong mid-level warm/moist advection and resultant isentropic ascent leading to a band of mixed precip. The latest NAM and GFS BUFKIT soundings have given more confidence to a period of light snow, sleet, and freezing rain as the mid-level warm air overruns shallow cold air below 925 mb. The question continues to be how soon will we saturate to allow precip to reach the surface? The NAM holds onto the low-level dry air until after about 08Z in most areas while the GFS scours it out about 2 hours earlier. Blended the latest NBM with the previous PoP forecast which brings the best chances for a wintry mix into NW Ohio after 04Z, across north central and NE Ohio after 07Z, and into far eastern Ohio and PA by 10Z. Any freezing rain or sleet will only last 2 hours or less in any one place as the band shifts E/NE through the region with ice amounts of a trace to 0.05 and snow amounts of a trace to a few tenths. The cold air lingers the longest over far NE Ohio and NW PA, so the highest amounts of snow and ice in the above mentioned ranges will likely occur in these areas. A changeover to rain will occur behind the warm front before the precip ends. Will mentioned this in the HWO. Lows Tuesday night will generally be in the upper 20s to low 30s. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... On Wednesday, low pressure of around 980-990mb will be located along the upper Mississippi Valley, with a warm front extending eastward from northwest-southeast Ohio. This warm front will make east- northeast progress through the day, located over western PA/NY by mid afternoon. A band of showers is expected to accompany this warm front as 925-850 frontogenesis and warm air advection loft provide isentropic forcing for ascent. With the forcing located ahead of the warm front, it`s likely showers will mainly occur during the morning hours. Due to strong warm air aloft and coinciding cold temperatures near the surface, we have introduced a chance of freezing rain with the leading edge of precipitation. Freezing rain chances should be limited to the morning hours. Precipitation chances become nil by the afternoon hours behind the warm front. With the frontal passage, southerly winds develop and strengthen, quickly raising temperatures into the 60s areawide, and perhaps even into the 70s for parts of northwest and central Ohio (think southwest of a Toledo to Mount Vernon line). This will be about 15 degrees above normal for this time of the year. The aforementioned low pressure continues to make eastward progression through the short term period, located along the Ontario/Quebec border just northeast of Lake Huron by Thursday afternoon. A strong pressure gradient may result in strong winds Wednesday night, with model guidance suggesting wind gusts as high as 30-35 knots for areas along and west of I-71. There almost could be equally strong gusts in norther Erie, PA County due to downsloping with southeast winds. A cold front extending from this low is expected to be located across northwest or north-central Ohio by late morning Thursday. Rain showers ahead of this cold front is expected to impact the area Wednesday night through Thursday evening. Some model guidance is suggesting the development of instability ahead of the cold front Thursday afternoon evening for the far northeast Ohio and northwest Pennyslvania, which could result in some thunderstorm development in these areas. With 50-60 knots of deep-layer shear, it may be possible that a storm or two could become strong to severe. There is lot of uncertainty with instability though and greatest chance for severe weather is likely to be east of our forecast area. Ensuing cold air advection will result in a drastic temperature drop Thursday night with Thursday highs of upper 50s to mid 60s dropping down to the mid 30s by late Thursday night into Friday morning. Scattered showers linger into Thursday night due to wrap around moisture and propagation of shortwave troughs within a broader upper- level trough. Colder temperatures could result in some rain/snow mix. && .LONG TERM /FRIDAY THROUGH MONDAY/... Broad upper-level trough with several shortwave troughs swirling around will result in scattered showers throughout the day Friday, with some lake enhancement adding to the potential in the snowbelt areas. A rain/snow mix is expected. The back edge of the upper-level trough exits the area to the east by 00Z Saturday, though some light lake effect snow could ling into Friday evening for northwest Pennsylvania. Surface high pressure builds across the area Friday night through Saturday, allowing for relatively quiet weather conditions during that time frame. A weak low pressure system is expected to move across the area some time Saturday evening through late Sunday morning. Saturday high temperatures are expected to be in the upper 40s, potential evening low 50s, so precipitation type expected to begin as rain. However, as the low passes to the south across the Ohio Valley, it`s possible that cold air advection on the northern end of this low may be enough for some wintry precipitation, though it`s unlikely that there will be much appreciable wintry precipitation. High pressure builds in for Sunday/Monday, allowing for more mostly quiet weather. && .AVIATION /00Z Tuesday THROUGH Saturday/... Diurnal lake effect snow showers and clouds are gradually dissipating with sunset. Expecting the activity to continue to weaken with time as high pressure builds east into the area overnight. Clearing skies will take place over the west with lingering scattered clouds in the east by sunrise. Otherwise, fair weather returns with VFR conditions for Tuesday. Winds are also diminishing to light and variable across the area for the overnight hours. As the high builds in, winds will shift around to a south-southeast direction from a Cleveland to Mansfield line west. Otherwise, northwest winds prevail east of that line. Outlook...Non-VFR possible within rain/snow through Wednesday morning. Non-VFR at times late Wednesday night through Friday. && .MARINE... Winds have diminished over the lakeshore waters in Ohio so will go ahead and drop the small craft advisory for these areas. Winds of 20 to 25 knots still being reported along the lakeshore of Pennsylvania up into New York and will hold on to advisory for the time being. Previous Discussion... High pressure ridge works is way east across the Great Lakes this evening into tonight. This will cause currently observed northwest winds of 15-25 knots to gradually weaken from west to east. Waves will follow a similar pattern with wave heights of 4-6 feet across the central and eastern basins this morning, diminishing to 1-3 feet by this evening. As waves dip below criteria, the Small Craft Advisory will gradually go away. Conditions will become quite pleasant across the lake Tuesday into Tuesday evening, before winds begin to again increase, this time from the southeast at 10-15 knots ahead of an approaching warm front. These winds will become southerly and strengthen behind the departing warm front on Wednesday and Wednesday night as low pressure approaches the region from the southwest, becoming 20-25 knots across the entire lake by Wednesday night. With offshore flow, expect the largest waves to remain along the northern portion of the Lake, although another Small Craft will likely be needed to account for the strong winds. Winds behind the departing cold front on Thursday into Friday will persist at 20-25 knots, but now from the west. Westerly winds of near 20 knots likely to persist through Friday. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...Small Craft Advisory until 1 AM EDT Tuesday for LEZ149. && $$ SYNOPSIS...Garuckas NEAR TERM...Garuckas/Lombardy SHORT TERM...Saunders LONG TERM...Saunders AVIATION...Lombardy MARINE...Saunders
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1150 PM EDT Mon Mar 28 2022 .AVIATION... VFR conditions are expected overnight through much of the day Tuesday as high pressure expands across the area from the west. Light northwest flow will become southeast Tuesday as the center of this high progresses to the east. Increasing elevated moisture/lift in advance of low pressure over the central CONUS will then bring an increasing chance for a wintry mix over the area by the end of the forecast period...generally after 03z-04z Tuesday night. For DTW...The chance of light wintry mix will increase late in the forecast with a gradually transition to rain as temperatures edge above freezing at the surface overnight Tuesday night. Otherwise, VFR with light winds overnight into Tuesday. .DTW THRESHOLD PROBABILITIES... * Medium in a light wintry mix of sleet/freezing rain developing in the 03z-07z time frame Tuesday night. * Medium for ceilings aob 5kft overnight Tuesday night. && .PREV DISCUSSION... Issued at 330 PM EDT Mon Mar 28 2022 DISCUSSION... Extremely dry airmass in place, as the 12z DTX sounding indicated a PW value of 0.08 inches, a daily record low value as a strong upper level PV anomaly exits east through Pennsylvania. Highly confluent upper level northwest flow will allow for high pressure (1029-1030 MB) to track through the Central Great Lakes tonight and through the eastern Great Lakes tomorrow. Favorable radiating night to result in min temperatures mostly in the teens. Although, with the current dew pts in single numbers, the coldest spots will probably sneak into the single numbers. Upper level low/energy tracking through far southern California this afternoon will be drawn northward as northern stream shortwave over Western Canada digs southeast into Eastern Montana late Tuesday. Excellent surge of moisture into southern Lower Michigan by midnight, as PW values increase to around 1 inch Tuesday night, ushered in by 60+ knot southwest jet at the 850 MB level over the western Ohio Valley. With the center of the high more or less due east or even southeast, increasing southeast surface winds will provide a feed of low level dry/cold air, but moist/warming mid levels in excess of 3 C in the 850-700 MB layer lifting through southeast Michigan 7-14z Wednesday should assure complete melting of the hydrometers south of M-59 by 10z. The warm advection arm based off the RAP looks to persist the longest along and north of I-69 where surface temperatures look to hold below freezing for an extended period, resulting in ice accumulations, but under quarter of an inch based on QPF of 3 tenths of an inch or less. Deepening of the low/cyclogensis to occur over the Great Lake Region Wednesday evening/night as some phasing/merging of height falls occurs. Moist warm conveyor belt and some modest instability will promote showers and possible embedded thunderstorms with the cold frontal passage. Cold advection to occur through Thursday night, with 850 MB temps lowering into the negative mid single numbers in the afternoon and -10 C or slightly colder by Friday morning, which also looks to hold steady during Friday as well. Local probabilistic guidance suggesting wind gusts around 40 MPH Thursday morning, which certainly is in play if sub 980 MB low over the northern Great Lakes materializes. A trend toward a zonal pattern over the Weekend suggests temperatures moderating, with the subtropical jet looking to be more active along the Gulf Coast States. MARINE... Winds and waves will decrease through the evening and overnight as an area of high pressure slides across the Great Lakes. Winds will be light out of the north tonight before going calm early Tuesday with the center of the high overhead. Winds will then flip around to the southeast late in the day the high pushes off to the east and we fall between the exiting ridge and the next strong low pressure system approaching the western Great Lakes. The warm front will swing up through the state Tuesday night and Wednesday bringing widespread precipitation and elevated winds through the end of the week. HYDROLOGY... A wintry mix of precipitation (mostly in the form of freezing rain) will overspread southeast Michigan late Tuesday evening and continue Tuesday night. Precipitation will change to rain early Wednesday morning, with generally light off and on showers during the day before a renewed round of widespread showers impacts the area Wednesday evening and Wednesday night. Isolated thunderstorms are also possible in this time period. Even so, total rainfall amounts are generally expected to remain under 1 inch, with areas across the Tri-Cities region having the best chance to reach near 1 inch. Flooding is not anticipated, but river rises and standing water/ minor nuisance flooding in low lying areas can be expected. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...NONE. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && $$ AVIATION.....99 DISCUSSION...SF MARINE.......DRK HYDROLOGY....SF You can obtain your latest National Weather Service forecasts online at
.Afternoon Area Forecast Discussion...

SHORT TERM /Tonight through Tuesday Night/... No significant forecast concerns or weather impacts expected in the short term period. Warming trend continues as upper ridge builds into the area. Very dry air still in place through tonight and early Tues, somewhat reinforced with weak wedge front and Ely sfc winds. Return of low level moisture from the south slow but steady Tues afternoon but not soon enough to preclude another high fire danger day over east central GA. Used blend of MAV/MET/ECS MOS with HRRR and HIRESWarw for dewpoints. Winds will be about the same as today which were weak enough to just preclude a Red Flag event. Will need to monitor conditions closely. Used MAV/NBM/NBM90Pct for winds and gusts. Fire Danger Statement will be issued later tonight after current event ends. SNELSON LONG TERM /Wednesday through Monday/... Long term forecast concerns continue to be focused on midweek system as occluded/cold frontal passage is progged to move through the area. Extended models continue to be in good agreement with overall timing and strength of short wave as it sweeps through the state Wednesday night through Thursday. For now, modeled high deep layer and low level shear is matched with extremely limited MUCAPE, inhibiting severe potential. At this time it appears the greatest threat for severe would be near onset Wednesday evening as lingering daytime destabilization attempts to support incoming convective line and then again on Thursday as the system exits the southeastern CWA. Forecast rainfall amounts continue to show around 1 to 1.5, with higher amounts generally over central Georgia. Even with all/most of this QPF expected in a 6-hr or less period, with the recent dry weather, this should not require much in the way of flooding concerns. Warm afternoon temperatures are expected Wednesday ahead of the front, but then trend back to near seasonal normals into the weekend. 31/lgb AVIATION... 00Z Update... VFR conditions are expected through the forecast period. Cloud cover has waned across north GA this evening, though mid-level and upper-level clouds are expected to spread back in from the north overnight. Have ATL going BKN060 at 09z and scattering out at 15z. Will see a wind shift from NW to NE around 05z as surface high pressure shifts eastward across the OH River Valley. Winds will be 5 kts or less overnight and will increase to 5-10 kts out of the E to SE on Tuesday afternoon. //ATL Confidence...00Z Update... High confidence on all elements. Martin && .PRELIMINARY POINT TEMPS/POPS... Athens 44 68 49 80 / 0 0 0 0 Atlanta 47 73 52 81 / 0 0 0 5 Blairsville 38 63 45 72 / 5 0 0 5 Cartersville 43 74 52 81 / 0 0 0 10 Columbus 51 83 56 85 / 0 0 0 5 Gainesville 45 66 48 78 / 0 0 0 0 Macon 47 79 54 85 / 0 0 0 0 Rome 43 75 51 82 / 0 0 0 20 Peachtree City 46 76 54 83 / 0 0 0 5 Vidalia 49 79 56 85 / 0 0 0 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Martin LONG TERM....31 AVIATION...Martin
Area Forecast Discussion
National Weather Service Goodland KS
908 PM MDT Mon Mar 28 2022 .UPDATE... Issued at 903 PM MDT Mon Mar 28 2022 Updated forecast to include patchy fog across eastern portion of CWA. Skies are remaining mostly clear in area with relatively deeper moisture as per DDC sounding and RAP low level forecasts. Potential for strong cooling and moisture pooling along convergent zone bisecting the area will at least increase the threat for fog enough to include in forecast. && .SHORT TERM...(This evening through Wednesday night) Issued at 233 PM MDT Mon Mar 28 2022 Across the Tri State area this afternoon, skies are a partly sunny to sunny mix as high clouds filter thru the area. A stationary front sits along the CO/KS border. This is allowing for southerly flow in KS/NE which is gusty at times over 25 mph winds along the front in Colorado are 10 mph or less. Temperatures range from the mid 70s west over to the mid 60s east. For the remainder of the afternoon, still looking for a few hours over south/southwest zones of elevated to near critical conditions. By sunset expecting RH values to increase as temps drop. Going into tonight, expecting much of the area to remain on the warm side of the front. Some model discrepancies to the timing of the front thru the cwa, which will impact chance for trw/rw over the area. Low moving along the front will traverse southern zones, putting those locales under elevated to near critical fire wx conditions for the afternoon hrs. Worse conditions expected to remains south of the cwa, despite seeing upper teens for rh and winds over 20 mph at times. No product issued for fire wx. SPC does have much of KS/CO in elevate/critical outlook. What is expected to occur will be showers with the potential for some thunderstorm activity. Drier air remains thru the early afternoon, with wrap-around moisture triggering showers and potential convection by late afternoon into the early evening. The latest Day 2 convective outlook from SPC has general thunder for much of the cwa, with a thin area of Marginal risk for areas east of Highway 283. Main threat is hail. With airmass being so dry at the potential onset, not looking for hail over an inch. As the front/system traverse the cwa Tuesday night into Wednesday, expecting colder air to infiltrate northern zones and wrap into the rest of the cwa going into Wednesday morning. Low qpf is forecast, but expect a changeover from rain showers to snow showers, with less than an inch accum. Ground temps too warm to impact roadways, but overpasses, bridges...etc could be impacted. Strong northerly flow will also accompany the changeover with the potential for some localized blowing snow. Strong winds persist into Wednesday when gusts around 50 mph are possible, impacting travelers on area roadways. Winds taper by the evening hours. For temps, the passage of a front through the area will give a wide range for highs Tuesday with upper 50s to lower 60s west thru the 70s in eastern zones. On Wednesday, mid 40s to lower 50s expected. Overnight lows tonight will range from the upper 30s into the mid 40s. Cooling trend thereafter, with lows Tuesday night in the upper 20s to the mid 30s. And for Wednesday night, lower to mid 20s. .LONG TERM...(Thursday through Monday) Issued at 145 PM MDT Mon Mar 28 2022 The period will start under shortwave ridging on Thursday, bringing dry conditions and temperatures back to near normal. However, the next fast moving shortwave trough will approach from the west and bring a chance for light rain and snow late Thursday night through Friday night. QPF with this system appears it will be fairly light, less than a tenth of an inch, and mainly in the form of light rain showers, but cannot rule out a mix or change to light snow Thursday night/Friday morning and again Friday night on the back side as temperatures drop into the 30s. However, little, if any, accumulation is expected. Friday may be breezy to windy behind the cold front with current model forecasts of north winds gusting to around 40 mph. Temperatures may be a little cooler than currently forecast with the clouds and precipitation. Upper flow over the weekend will be mostly zonal to slight ridging. That will result in mostly sunny skies and temperatures near to slightly above normal. Next trough in the progressive pattern will dig into the Four Corners on Sunday and kick into the plains Sunday night and Monday. It will bring another chance of scattered light rain showers, or perhaps a few thunderstorms with MUCAPE increasing during that time across primarily eastern part of the forecast area. Temperatures on Monday will continue to be slightly above normal. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 527 PM MDT Mon Mar 28 2022 VFR conditions will prevail at KGLD through at least 18z, with potential for MVFR conditions increasing through the afternoon as showers develop. Forecast for MCK is somewhat more complicated as area of LLWS will develop just above near surface inversion and persist into the early morning hours. Additionally, potential exists for development of low stratus or even fog between 10 and 15 UTC. Currently appears low MVFR stratus the most likely scenario, but will have to monitor area closely tonight. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JRM SHORT TERM...JN LONG TERM...024 AVIATION...JRM
Area Forecast Discussion
National Weather Service Green Bay WI
1047 PM CDT Mon Mar 28 2022 Updated aviation portion for 06Z TAF issuance .SYNOPSIS... Issued at 251 PM CDT Mon Mar 28 2022 A major storm system crossing the region will bring a round of significant precipitation to the area mid-week. Much of it could be wintry, especially across the north. Some thunderstorms are also possible, especially in central and east-central Wisconsin. A progressive and very energetic southern stream of a split flow regime will dominate the weather across the CONUS during the period. A strong upper trough embedded within the southern stream will bring significant precipitation to the area mid-week, resulting in above normal amounts. Temperatures will vary between modestly below and slightly above normal during the period. && .SHORT TERM...Tonight and Tuesday Issued at 251 PM CDT Mon Mar 28 2022 The latest RAP analysis and satellite/radar imagery show arctic high pressure centered across Wisconsin early this afternoon. Clear skies prevail over the eastern half of the state, but mid and high clouds are already approaching the Minnesota/Wisconsin border along the leading edge of isentropic ascent well ahead of the next system. However, very dry air as noted by dewpoints in the 20s and 30s, exist into Oklahoma and Arkansas, so it`s doubtful that radar returns over Iowa and Missouri are reaching the ground. As the high departs and the next system moves closer to the region, cloud trends and timing of precip are the main forecast concerns. Tonight...High pressure will remain present across the region this evening before shifting to the eastern Great Lakes late. Westerly winds aloft will be pushing the upstream mid and high level clouds into the area, which will gradually lower through the night. A wedge of dry air will remain below 750mb, so the chance of precip will remain too low to mention. Low temps will likely occur by late evening or early overnight before the thickening cloud cover causes temps to stall or even rise some. Min temps will range from the middle single digits near the U.P. border to the low 20s over the Fox Valley. Tuesday...Low level winds will shift to the southeast and become breezy, as an influx of moisture in the 850-700mb layer surges northeast into the region in the afternoon. With the thickening cloud cover and onshore winds, temps will struggle to warm over the Fox Valley and northeast WI, but should still see temps a little warmer than today. Because the departing airmass is quite dry, think models are a little too aggressive in generating precip in the afternoon and have slowed down precip chances. Highs will generally be in the mid and upper 30s. .LONG TERM...Tuesday Night Through Monday Issued at 251 PM CDT Mon Mar 28 2022 The primary long-term forecast issues remains the complex system crossing the area mid-week. The models` handling of the initial band of precipitation that will move through the area Tuesday night into Wednesday morning has remained fairly consistent, though still concerned they may be getting it here a little too fast given that the primary upper level energy is just now reaching the West Coast. A warm layer aloft will surge northeast across the area Tuesday evening, limiting any snow to near the onset of the precipitation. Precipitation later in the night will depend on boundary layer temperatures (RA vs FZRA), and the depth/strength of a negative energy area below the melting layer (PL vs FZRA). There is still uncertainty about precip amounts, which will affect the amount of icing that occurs if precipitation is mainly FZRA. All things considered, there is enough potential for AOA 0.25 inch of icing to warrant posting a Winter Storm Watch for N-C into far NE WI. The initial frontal wave/inverted trough will weaken and slowly shift across southern Wisconsin Wednesday. Precipitation across the forecast area should be mainly rain, with some thunderstorms also possible. Colder air will be settling south into the region at low-levels Wednesday night into Thursday as strong cyclogenesis occurs just to our east, and strong ascent will help to overcome any lingering warm layer aloft--except possibly over the far eastern part of the area. So the thermal profile will favor rain changing to snow. But the amount and location of precipitation is highly uncertain due to the interactions that will be occurring between southern stream shortwave energy rotating around the large scale trough, and possible phasing of a northern stream shortwave. The potential exists for a swath of 4-8 inches of heavy wet snow. The best guess right now is that it would occur from C-NE WI, but that could easily shift west or east depending on exactly how the system evolves. Given the uncertainty, will hold off including that time period in any headlines this far in advance. && .AVIATION...for 06Z TAF Issuance Issued at 1046 PM CDT Mon Mar 28 2022 VFR flying conditions are expected through most of the TAF period, with conditions starting to deteriorate Tuesday evening, after 00Z. At 340Z this evening, skies were still mainly clear as high pressure slid off to the east. Overnight, middle level clouds just off to the west will overspread the area from west to east. Winds increase from the southeast Tuesday morning with gusts to around 25 kts. More impactful weather will arrive Tuesday evening and overnight as a mix of wintry precipitation will lead to lowering cigs and vsbys. Conditions will likely drop to MVFR Tuesday evening, with further deterioration beyond the TAF period Tuesday night into Wednesday morning. && .GRB WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from Tuesday evening through Wednesday morning for WIZ005-010>013-018-019-021. && $$ SYNOPSIS.......Skowronski SHORT TERM.....MPC LONG TERM......Skowronski AVIATION.......KLJ
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
1024 PM EDT Mon Mar 28 2022 .SYNOPSIS... Gusty northwest winds will continue through Tuesday as low pressure will be slow to exit the Canadian Maritimes. High pressure slowly builds in from the west Tuesday before cresting over the area on Wednesday. A warm front will then push north through the area Wednesday night bringing chances for a light wintry mix followed by a warming trend Thursday and Friday before a cold front crosses the area. && .NEAR TERM /UNTIL 7 AM TUESDAY MORNING/... Update...Upper trof axis is starting to cross the forecast area now...and upslope snow showers are becoming more prevalent as a result. Some very light snow or snow showers will drift southward across the Midcoast as the embedded S/WV moves thru there...and so I have added some isolated snow showers there. Otherwise no major changes to the forecast. Previous discussion...A northwest gradient will persist over northern New England tonight through Tuesday night as low pressure in the Canadian Maritimes is slow to exit into the North Atlantic and high pressure over the Great Lakes slowly advances eastward. Latest water vapor imagery shows a pair of upper lows rotating over the Northeast. Latest radar shows numerous snow showers across Upstate NY and PA associated with one of these upper lows as cooling temps aloft and surface heating has allowed for a 100-200 J/kg of MU CAPE. CAMs are much less bullish on instability in our CWA with CAPE topping out around 50 J/kg over southern NH and SW Maine late this afternoon. The upper low over Upstate NY and PA will pivot across southern New England this evening bringing increasing chances for snow showers across the forecast area with the greatest chances across the mountains and portions of southern New Hampshire. The latest RAP analysis does paint some modest snow squall parameter values across southern NH and SW Maine, although without a notable pressure fall/rise couplet or lifting mechanism the threat for snow squalls is low. Overall expect snow shower activity to pick up through this evening with those that see snow showers only receiving a coating to less than an inch of snow while a couple inches remain possible in the higher terrain of the White Mountains. Temperatures aloft will continue to cool this evening bottoming out around -18C at H8. The upper lows will consolidate over the Gulf of Maine this evening into tonight as it treks toward Nova Scotia by Tuesday morning. Snow shower activity will be confined to the mountains overnight with skies turning party cloudy downstream of the mountains. Winds will remain elevated overnight limiting radiational cooling, although it will be quite cold for this time of year with lows in single digits across the north and teens across the south. && .SHORT TERM /7 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... On Tuesday the northwest gradient will still be over New England providing another breezy day. Northwest winds will run steady between 10 and 20 mph with gusts 25 to 30 mph. Mostly sunny skies are expected downstream of the mountains as high pressure gradually builds in from the west while upslope flow will maintain clouds in the mountains. As temperatures aloft creep upwards tomorrow expect highs to be warmer than today but still below normal for this time of year. Northern areas will stay in the 20s while areas south of the mountains will rise into the low to mid 30s. Winds may again limit the radiational cooling potential Tuesday night with lows ranging from near 10F across the north to near 20F across southern and coastal areas. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Troughing will shift north and east over the Canadian Maritimes as an upper ridge builds over the Eastern Seaboard on Wednesday while another trough digs into the Northern Plains and Great Lakes region. Locally, our wind profile will switch back to west to southwesterly, which will allow Wednesday`s temperatures to rebound back into the mid-upper 40s for southern areas and lower 40s across the north. Wednesday will start out mostly sunny, but cloud cover will increase in the afternoon and evening as the atmosphere moistens in a top- fashion ahead of our next storm system that will increase precip chances from Wednesday evening into Friday. The first wave of precip looks to arrive Wednesday evening and night ahead of a warm front with temperature profiles initially cold enough to support a period of snow or freezing rain (supported by a low-level warm nose aloft), and confidence has increased enough to where we have officially added mention of mixed precip to the forecast. Amounts look minimal for the time being, but there still could be some slick travel, especially across the foothills and mountains where duration is expected to be longest. Global models indicate a period of mid-level drying as temps continue to warm above freezing through Thursday morning, but with saturated low levels it will remain cloudy with some drizzle also possible. The previously mentioned trough will then move across the Great Lakes and through New England while the surface low lifts north from the Great Lakes toward Hudson Bay on Thursday and a secondary low forms near the ME Coast and heads toward the Maritimes on Friday. Waves of energy rotating around the parent trough will provide the main source of lift, ramping up precip chances ramp later on Thursday into Thursday night as moisture increases, but we`ll be well into the warm sector, so precip type is expected to be rain. However, as the secondary low lifts north on Friday, a cold front will sweep through the area, and colder air filtering behind it could result in a switch back to snow showers, mainly toward the mountains and higher terrain. For the rest of the area, the trend will be for precip chances to diminish through the day. Max temps Thurs should be able to reach the mid-upper 40s on Thurs, possibly low 50s toward southern NH/ME. On Friday, temps are expected to reach the 50s before temps start dropping behind the cold front. As far as rainfall amounts/timing, GFS/ECMWF ensemble means are in pretty good agreement with rainfall amounts generally ranging from 0.25-0.50" and primarily in the Thurs. evening through Fri. morning window. For the weekend and into early next week, except for some upslope snow showers across the mountains, drier air will keep any mention of precip out of the forecast. NBM temperatures aren`t showing much of a cool down as highs for Saturday are forecast to be in the 40s and then back into the 50s for Sunday and Monday. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... Short Term...Upslope flow through tonight may bring periods of MVFR cigs to KHIE. Scattered snow showers are expected through this evening and cannot rule out brief restrictions in -SHSN while confidence is not high enough to put restrictions in the TAF besides at KHIE. Any snow shower activity diminishes overnight with VFR expected for all tonight through Tuesday night. Long Term...VFR conditions expected on Wednesday. MVFR/IFR restrictions are then possible starting Wednesday evening into Thursday morning as ceilings are forecast to gradually lower and some light snow and/or mixed precip moves across the region. IFR ceilings, possibly LIFR, are expected on Thursday and into the early part of Friday before conditions improve Friday afternoon and evening. && .MARINE... Short Term...Gusty northwest winds are expected to continue tonight through Tuesday night bringing SCA conditions. Cold air advection over the waters tonight will also bring some areas of light freezing spray. Long Term...Conditions look to remain below SCA conditions through early Thursday, but increasing southerly winds will build seas to the 5-7 ft range late Thursday into Friday, likely requiring a SCA. Winds will veer westerly behind a cold front on Friday with SCA conditions continuing into Friday night. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ150>154. && $$ NEAR TERM...Legro
Area Forecast Discussion
National Weather Service Lincoln IL
756 PM CDT Mon Mar 28 2022 .SYNOPSIS... Issued at 756 PM CDT Mon Mar 28 2022 A strong low pressure system will develop near the Rockies, and work into the Midwest over the next few days. Strong winds and widespread rainfall will accompany the system Tuesday into Thursday. A few strong storms and heavy rainfall also appear possible for some on Wednesday. && .UPDATE... Issued at 756 PM CDT Mon Mar 28 2022 East/southeast winds are expected to pick up during the night as the high pressure continues to pull out of our region, with gusts 20-25 mph expected by sunrise. This, as well as the high clouds, will keep temperatures from falling off too much after midnight. Latest HRRR is joining in with the 18Z NAM Nest model in trying to get a few showers going in western Illinois toward sunrise, but with dew points only rising into the lower 20s in that area, anything reaching the ground will be very light. Made some minor adjustments for tonight, mainly with the winds, but general forecast trends are still on track. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 246 PM CDT Mon Mar 28 2022 Quiet and cool conditions are ongoing across the area this afternoon as high pressure remains in control. High temperatures as of 2 PM were sitting in the upper 30s to 40s with light east winds in place. Cloud cover continues to increase through tonight as WAA feeds northward. Upper ridging positioned over the western US will work east going into Tuesday, pushing the surface high toward the eastern Great Lakes. Further west, a longwave upper trough rotating over the southwest US will lower heights over the Rockies, spinning up a surface low in the lee of the mountains. The pressure gradient will tighten here locally between the developing surface low and departing high, increasing winds speeds. Southeast winds look to be pretty breezy with gusts upwards of 30 mph possible especially during the afternoon hours. Warm air will advect northward on Tuesday as a warm front approaches the area. This has made for a tricky high temperature forecast for Tuesday as models still differ on how far north the front will get during the day before lifting through the area going into the nighttime hours. High temperatures will be warmest across southern counties with values looking to warm into the 50s. However, temperatures will remain cooler likely only topping out around the middle 40s across the north resulting in a large gradient across the area. WAA and isentropic lift will lead to the development of widely scattered rain showers ahead of the front`s arrival during the daytime hours. && .LONG TERM...(Tuesday night through Monday) ISSUED AT 246 PM CDT Mon Mar 28 2022 The aforementioned low will approach the area late Tuesday night into Wednesday, sending a cold front through sometime later in the afternoon or evening. Wednesday looks to be the warmest day of the week with most of the area expected to be in the 60s to even low 70s for some despite cloud cover. Precipitation chances will increase ahead of the front, with scattered storms also possible. Model guidance still keeps instability pretty limited with this system, however strong wind shear will be present. Windy conditions are expected once again on Wednesday with south-southwest winds looking to be the strongest ahead of the front`s arrival. Ensemble guidance is showing mean wind gusts especially across eastern parts of the state of 40+ mph with some members even insisting on higher magnitudes. The severe weather threat appears limited due to lack of instability, however a 50-60 kt LLJ may be able to make it`s way down to the surface with any stronger storms despite lack of organization. Because of this, a marginal risk of severe storms is focused across southeast IL. The strong winds will pull a plethora of Gulf moisture northward, allowing PWATs to surge well above 1". QPF amounts look to range from about 1-1.5". The flooding threat looks to be limited thanks to the quick movement of the system and recent drier conditions. Albeit, locally heavy rainfall may lead to localized low-land flooding and river rises. Because of this a marginal risk for excessive rainfall is in place for Wednesday. Light precipitation chances look to continue into Thursday as a few waves of energy rotate through the large scale trough that will be positioned over the Great Lakes Region. Temperatures will be cooler on Thursday as northwest flow sets up aloft, so cannot completely rule out a few snowflakes mixing in with the rain across northern counties early late Wednesday night into Thursday morning. Winds will remain breezy on Thursday as the backside of the low swings through the area. West-northwest winds look to gust up to 35 mph. Cooler weather sticks around for the end of the week and into the weekend before temperatures gradually rebound some for the start of the new week. Small precipitation chances exist on Saturday tied to a shortwave looking to move through the country`s midsection. However, there remains uncertainty on this as model guidance has differing views on if it will take a more southern or northern track. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 705 PM CDT Mon Mar 28 2022 Quiet conditions in the short term for the evening TAF set, but winds start to pick up after 06Z as high pressure exits the area. East/southeast winds should be gusting to around 20 knots before 12Z and will be closer to 30 knots by 18Z. Expect ceilings to gradually lower, mainly staying above 5,000 feet, though KPIA/KSPI could be getting close to MVFR levels by the end of the forecast period. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SYNOPSIS...NMB/Geelhart SHORT TERM...NMB LONG TERM...NMB AVIATION...Geelhart
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
921 PM EDT Mon Mar 28 2022 .DISCUSSION... Tonight...Some transitory thin high clouds will move across the area by midnight with clear skies for the rest of tonight. It will be cool again overnight with min temps in the M-U 50s, but with light winds and somewhat higher humidity. HRRR guid is indicating some fog trying to develop by daybreak over W Central Fl with some east drift toward the center of the state by daybreak. Some locally patchy, largely shallow fog wl be possible into early Tue morning, though more widespread fog is not expected. Tue...High pressure over the peninsula early in the period will venture into the western Atlc providing a light, but onshore flow areawide as the pressure gradient remains weak. Dry conditions persist, though we will continue a gradual warming trend as highs will be near 80 along the coast and M-U 80s well into the interior. && .AVIATION...VFR. with W/NW wind 5 to 10kts. The pressure gradient remains light on Tue, though winds become onshore areawide during the aftn as high pressure moves over the western Atlc. && .MARINE...Tonight...A small nocturnal surge of S/SW flow 10-15 knots expected this evening, becoming northwest late. Seas up to 3-4 ft in the Gulf Stream. Seas near shore will be near ~2 ft. Tue...High pressure crosses the Florida peninsula emerging into the western Atlc. Onshore flow around 10 kts in the afternoon as the sea breeze develops. Dry conditions persist. Seas 2-3 ft. && .FIRE WEATHER...Tue...Continued slow modification of the airmass, though afternoon min RHs will still fall into the M-U 20s well into the interior (along Kissimmee River) and 40-50pct at the immediate coast, thanks in part to an onshore flow developing from the afternoon sea breeze. Wednesday...Minimum RHs continue to recover slowly, but will still drop into the upper 30s, possibly mid 30s, through the far interior in the afternoon. In addition, winds are expected to increase to 15- 20 mph mid week as the pressure gradient tightens ahead of an approaching front. This will bring the western portions of the interior counties to near Red Flag criteria. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ JP/KF
...Updated Aviation Forecast Discussion...

.DISCUSSION... Issued at 300 PM CDT Mon Mar 28 2022 Lots of things to be concerned with in the forecast the next few days, which include the following: Chance of severe storms for tomorrow afternoon and evening, high temperatures tomorrow, potential for low clouds, drizzle and fog late tonight into Tuesday morning, Fire Danger for parts of southeast NE Tuesday afternoon, chance for light snow or rain/snow mix Wednesday night. Latest water vapor loop in combination with recent RAP model initializations early this afternoon showed a strong closed low off the CA coast and mid level ridging over the high Plains. That system will be just west of the AZ/CA border tomorrow morning, while a shortwave trough in a northern stream of energy pushes to Saskatchewan and MT. Expect somewhat of a phasing and mid tropospheric wave intensification over western NE Tuesday afternoon while a surface low deepens over south central NE. There is a fair amount of model spread in the details for tomorrow. If we end up cooler, the severe weather threat may be less. For now, we will continue to go with the SPC outlook and mention a chance for severe storms, mainly from 4 pm to midnight. The RAP13 model output does indicate some areas of MUCAPE greater than 1000 J/kg in our area in the afternoon and evening. Forcing to generate lift seems sufficient with decent mid level lapse rates. Current dewpoints this afternoon are pretty low, in the mid teens to lower 20s, resulting in very high fire danger which may be in in the Extreme category briefly. Dewpoints are still pretty low even down in KS, but values were in the 40s and 50s across OK. We will count on at least some moisture return Tuesday, using a blend of NBM and RAP. Highs should range from upper 50s near the SD border to upper 70s or around 80 at the KS border. Colder and drier air will move back in after the cold front passes Tuesday night, and Wednesday will be cool as well - with highs mainly in the 40s. Parts of northeast NE could see a rain/snow mix Wednesday morning. All of the area will have a 20 to 40 percent chance of light snow or a rain/snow mix Wednesday night with lows in the 20s, but little if any snow accumulation is expected at this time. Model blend suggests increasing chances for precipitation Friday afternoon into Saturday morning, but again amounts look pretty light - under a quarter of an inch at most spots. Highs in the 40s to lower 50s Thursday should moderate to 50s and lower 60s for Friday/Saturday/Sunday. Models start to have timing differences in the mid level pattern for early next week. We will include some low POPs Sunday and Monday but confidence is not high. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 542 PM CDT Mon Mar 28 2022 VFR conditions at TAF issuance with southeast wind gusts at 17 to 27 knots. LLWS develops at KLNK 07-15z, and KOMA 11-15z when winds at 2000 feet will be from the southeast around 150 degrees at 35 to 45 knots. And then low IFR clouds develop at KLNK 15-17z, and 15-20z at KOFK. Not confident enough to mention any precipitation at this point since it`s only a 20-30% chance, but could see spotty showers at KLNK/KOMA after 18z. Should be able to further refine rainfall potential with later issuances. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Miller AVIATION...DeWald
Area Forecast Discussion
National Weather Service Tucson AZ
233 PM MST Mon Mar 28 2022 .SYNOPSIS...A storm system will impact the area, bringing gusty winds and a good chance of valley rain and mountain snow showers with much cooler temperatures on Tuesday. This system departs Wednesday with temperatures rebounding to near normal to close out March and begin April. && .DISCUSSION...Water vapor imagery shows moisture overspreading Arizona ahead of a deep upper low that is approaching the California coastline. Lots of virga showing up on radar, but the boundary layer is too dry for any drops to survive to the surface. Dewpoints are currently in the 10-20 degree range across the valleys. The HRRR and other hi-res guidance indicates we may see a few light showers this evening, primarily at the higher elevations from Tucson eastward. Winds are the other story with a Red Flag Warning in effect until 8pm. Strongest winds have been out west, but it`s a bit of a borderline event. Thick cloud cover has prevented sufficient deep layer mixing. The tightest 700mb gradient doesn`t swing through until tonight, which likely keeps winds from decreasing per our usual nocturnal trend. This is especially true in the mountains. Tomorrow is really the main course as the upper low swings across the region. Winds remain gusty, with the area of strongest winds shifting east. This may produce patches of blowing dust in the problem areas in eastern Cochise County, depending on how showers evolve. The best chance for rain occurs during the morning and afternoon, spreading from west to east across the area. Some moderate to heavy showers will be possible. This is due to 200-300 J/kg CAPE and a generous amount of wind shear to keep storms ventilated. HREF shows a 70% bullseye of 4-hr thunderstorm probabilities in eastern Pinal County, with lesser chances spreading out from there. The stronger storms could also drop some small hail. High temperatures also dramatically decrease, topping out 15-20 degrees below normal for this time of year. Snowfall is the last thing worth mentioning. With snow levels at 6-7k feet, only the mountain tops will see snow. Depending on the location, amounts generally range 3-6" with the higher amounts toward the White Mountains. By Wednesday, much of the area dries out save for a lingering snow shower in the Whites. Winds remain a bit breezy out east, becoming more seasonal by Thursday and beyond. Temperatures warm each day as ridging attempts to build back in. By the weekend, high temperatures should be back above normal with a continuation of dry weather. && .AVIATION...Valid through 30/00Z. BKN-OVC clouds AOA 20k AGL throughout the region with ceilings lowering down to 10k ft AGL after 29/03z. Ceilings lower again due to approaching front after 29/12z to AOA 6k ft AGL with brief pockets of 3k ft AGL from -SHRA through the forecast period. Radar shows virga from the west and will fill in towards the east through the night. ISOLD -SHRA can develop after 28/22z, but the main line of -SHRA from the front starts after 29/12z through the forecast period. There is some instability after 29/12z for a slight chance of ISOLD TSRA mainly confined north of the Catalina Mountains. Mountain obscuration and lower ceilings near 2k ft AGL is possible from the -SHRA. SFC winds will be generally SWLY with speeds of 15-20 kts and gusts up to 30-35 kts through majority forecast period. 18z HRRR has FROPA occuring 29/22z with the winds shifting from the NW. Moderate confidence on the timing for this forecast period. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A storm system will result in strong and gusty winds at times through tomorrow. Some showers are possible tonight, but the best chances will occur Tuesday morning and afternoon across the entire forecast area. A few embedded thunderstorms will also be possible. Much colder temperatures are expected Tuesday, with high temperatures 15-20 degrees below normal. A warming trend then takes place late this week, for a return to near normal temperatures. && .CLIMATE...This past Saturday Tucson recorded a high of 95 degrees. The forecast high tomorrow is 61 or 62 degrees, likely to occur after midnight. The last time Tucson saw a drop in high temperatures of 30+ degrees over a three day period during March was back in 2012. && .TWC WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MST this evening for AZZ150>154. && $$ Public...Howlett Aviation...Strongman Fire Weather....Howlett Visit us on Facebook...Twitter...YouTube...and at