Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/25/23


Area Forecast Discussion
National Weather Service La Crosse WI
1000 PM CDT Mon Apr 24 2023 .DISCUSSION...(This evening through Monday) Issued at 254 PM CDT Mon Apr 24 2023 Key Messages: - Moderate to major flooding continues along the Mississippi River. The river is forecast to crest from north to south throughout the week. The biggest river forecast uncertainty is how much precipitation will fall late this week through the weekend, and how this will impact river levels. - High pressure builds in mid-week bringing warmer (near-normal) temperatures and a couple of dry days. - Another weekend of periodic precipitation chances ahead. TONIGHT-TUESDAY: Despite surface high pressure building across the region, the Upper Mississippi Valley will remain on the periphery of a mid-level trough into Tuesday. Scattered generally diurnal showers will gradually diminish through early evening beneath the mid-level cold pool as a shortwave trough rotates across northern WI. The highest concentration of showers will be across WI, with decreasing coverage to the south and west. Diurnal cumulus will likely develop again on Tuesday, but shower chances will decrease without the aid of a stronger shortwave trough as heights begin to rise behind the slowly departing trough. DRY MID-WEEK: High pressure persists through mid-week with temperatures warming to near-normal. Subsidence will work to keep the region dry into Thursday. Thursday looks to be the warmest day of the week with high temperatures in the low to mid 60s currently in the forecast. PERIODIC PRECIPITATION CHANCES THURSDAY-MONDAY: A series of shortwave troughs embedded in an amplifying longwave trough will lead to periodic precipitation chances later this week. The first round of rain comes Thursday across parts of central Wisconsin, followed by more widespread scattered precipitation chances this weekend into early next week. It is a very similar setup to what we saw this past weekend. There is still over half an inch of spread in the total QPF between the GEFS and EPS with the GEFS producing 1.69" and the EPS totaling up to 1.15" in north- central Wisconsin by Monday evening. The GEFS also has a larger footprint of precipitation one inch or more, with the EPS favoring a much drier solution across the southern half of the forecast area. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1000 PM CDT Mon Apr 24 2023 CIGS: BKN VFR slowly scattering out late this evening. RAP/NAM still hint at the potential for low stratus to push west out of eastern WI, but not as enthusiastic as earlier and not much support from the SREF. Will hold with VFR. KLSE could see another diurnally driven BKN deck Tue afternoon, WX/vsby: The HRRR suggests a smattering of showers would be possible Tue afternoon, but not as widespread and not favored by most of the other CAMS models. Winds: looking to stay on the lighter side (under 10 kts) from the north to northeast. && .HYDROLOGY... Issued at 530 AM CDT Mon Apr 24 2023 The mainstem of the Mississippi River is forecast to continue rising this week with several locations in Moderate and Major flooding levels. The latest flood statements have been updated with the most recent stages. These river forecasts include the next 24 hours of anticipated precipitation. The next chance for significant precipitation could occur Friday into the weekend. Probabilities for 0.50" or more are 60 to 75% with an inch or more 30 to 45%, however there remains a large spread in solutions related to placement and amounts, so continue to check back for updates. Melting snow and rain continues to work through the Mississippi River system across parts of MN and northern WI. Any additional rainfall could affect river stage forecasts and prolong the time period rivers remain above flood stage. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ DISCUSSION...KAA/JM AVIATION...Rieck HYDROLOGY...Zapotocny
Area Forecast Discussion...UPDATED
National Weather Service Glasgow MT
758 PM MDT Mon Apr 24 2023 .DISCUSSION... Evening Update: Models not very helpful with current isolated and disorganized rain showers out there. Made some adjustments this evening through tomorrow morning, increasing PoPs to err on the side of caution. When showers actually show up in the models into our western zones for tomorrow afternoon, the HRRR model seems to be the only one showing thunderstorm outflow wind boundaries coming out of the Little Rockies. Would not be surprised to see a few isolated thunderstorms there. Don`t think it will make it all the way to Glasgow. Bears watching and re-visiting. ----BMickelson Previous discussion: Active pattern is expected mainly Wednesday and Thursday this week, so hang on for the ride. The upper air pattern today has a ridge over the West coast with a disturbance dropping southeast across the central Rockies. Rainshowers are expected to stay just southwest then south of the CWA through tonight. Then pieces of energy over Alaska drop into western Canada tonight and to our north Wednesday and Thursday. This will send a couple of cold fronts through, the first one arriving late Tuesday Night/early Wednesday. Sensible weather will come in the form of mainly wind. It will switch to the NW Wednesday morning and increase during the day especially over the NE zones with gusts to around 40 mph. Another cold front will drop in early Thursday. This disturbance will have more moisture to work with for the chance of showers and the possibility of non-severe thunderstorms in the eastern zones. An upper trough will reside to our east with enough cold air for the slight possibility of snow late Thursday Night/Friday morning. Another cold front drops across the area Saturday with just NW winds with this one. The upper air pattern will have a high amplitude with a cold airmass to our east and an upper ridge bringing warm and dry conditions over the Pacific NW. TFJ && .AVIATION... UPDATED: 0200Z, Monday night, April 24th FLIGHT CAT RANGE: VFR DISCUSSION: Look for SCT-BKN mid and high clouds tonight and isolated disorganized rain showers slowly diminishing overnight. Another round of isolated rain showers and a few small thunderstorms will approach from the west by Tuesday afternoon, but should fizzle to only vicinity rain showers for KGGW and KGDV by Tuesday evening. WIND: E/ESE winds 15-25 knots this evening then decreasing to SE Tuesday at 10-15 kts. TFJ/BMickelson && .HYDROLOGY... Updated Monday PM, April 24th Hydrology concerns continue to gradually decrease as water levels continue falling this week. Milk River has dropped below the action stage of 21 feet at Tampico; dropped to around 28 feet in minor flooding at Glasgow; and dropped to near 21 feet barely in minor flood stage at Nashua. Glasgow will drop below minor flood stage of 25 feet sometime on Thursday this week. Nashua will drop down below minor flood stage of 20 feet overnight tonight. For the latest flood/river gauge information, see our AHPS page at www.water.weather.gov/ahps2/index.php?wfo=ggw ----BMickelson && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ weather.gov/glasgow
Area Forecast Discussion
National Weather Service Lincoln IL
738 PM CDT Mon Apr 24 2023 .SYNOPSIS... Issued at 731 PM CDT Mon Apr 24 2023 Showers will become widespread near and north of I-74 through the night, but areas further south will see lesser amounts of rain as the air remains fairly dry. The showers are expected to become more widely scattered on Tuesday, as a cold front drops southward through the area. Mid week should largely be dry, before the risk of showers begins to expand across the region late in the work week. && .UPDATE... Issued at 738 PM CDT Mon Apr 24 2023 Despite the impressive amount of radar echoes to our north and northwest, little in the way of rain is making it to the surface. Our evening balloon sounding shows quite a bit of dry air below 700 mb, which is the source of the issue. With time this evening, moistening of the column near/north of I-74 will take place. However, further south, RAP soundings from Springfield remain fairly dry below 5,000 feet into tomorrow morning. Main forecast update this evening was to sharpen up the PoP trends. Temperatures and winds are largely on track. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 300 PM CDT Mon Apr 24 2023 Mid afternoon surface map shows a warm front over central Nebraska into southern IA of NE/IA and into nw IL while 1023 mb high pressure was near the IN/Ohio border and ridging sw into the mid MS river valley and Ozarks. Orientation of high pressure ridge has cut off low level moisture return into central IL as dewpoints were only in the 20s with temps in the mid to upper 50s. Scattered to broken high level cumulus clouds with bases of 7-10k ft were along and west of highway 51 and just east of IL too, so eastern IL currently enjoying more sunshine this afternoon. Weak warm air advection driven rain showers to spread eastward from southern IA/northern MO into central IL during this evening and mainly affect areas north of a Springfield to Terre Haute line tonight. SPC day1 outlook has thunderstorms possible tonight over southern IA/northern MO. Added patchy fog to nw CWA overnight per trend of HRRR models with vsbys and ceilings lowering in north side of warm front. Lows overnight in the low to mid 40s central IL and around 40 in southeast IL where less cloud cover and lighter winds, with upper 30s over the Wabash river valley. As weak surface low pressure passes by on Tue it will push the front back south as a cold front and into southeast IL during Tue afternoon. Weakening forcing and lack of good moisture to limit chances of rain showers so just isolated to scattered showers pushing further south during the day Tue. Guidance has trended cooler for highs in central IL on Tue with upper 50s to near 60F, while near 65F from highway 51 south. .LONG TERM...(Tuesday night through Monday) ISSUED AT 315 PM CDT Mon Apr 24 2023 High pressure ridge over western Ontario nosing southward into IL on Tue night and Wed to return dry conditions to the area with decreasing clouds from the north Tue night and Wed morning. Lows Tue night in the mid to upper 30s in central IL (mid 30s from I-74 ne where patchy frost possible overnight if NE winds diminish enough, though currently we have them near 10 mph) and lower 40s in southeast IL where clouds linger longer. Highs Wed mostly in the lower 60s, with some upper 50s ne of I-74. Another cool night Wed night in the upper 30s/lower 40s. Could be another chance of patchy frost over far ne CWA overnight Wed night where less cloud cover expected. Medium range models show an active southern stream with a storm system moving into the lower MS/TN river valley Thu. This will increase clouds Wed night and Thu with chance of rain showers into southern counties Thu afternoon and areas from I-55 east Thu night. Thunderstorm chances appear to stay south of I-64 Thu afternoon/evening as instability is much weaker over our CWA. Highs Thu in the low to mid 60s, coolest in southeast IL where higher rain chances. Highs in the mid to upper 60s on Friday. A strong cutoff upper level low digs/develops over the central/southern plains Fri night and shifts east toward the MS river valley on Sat. Some models like ECMWF and GEM models have 2 cutoff lows by Sat evening with one near WI and another in the low MS river valley, while GFS shows one strong cutoff low near central IL. Either way it looks like showers will be likely moving into area during Friday night and Saturday along with cooler temperatures with highs Sat in the upper 50s to near 60F. Cool highs in the mid to upper 50s Sunday and Monday, and could see lingering chance of light rain showers on back side of strong upper level low moving into the central Great Lakes and mid Atlantic States by Sunday evening. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 620 PM CDT Mon Apr 24 2023 A warm front will be setting up near KPIA/KBMI this evening, with showers expanding along the boundary and ceilings lowering. Greatest impacts will be with MVFR ceilings at KPIA/KBMI toward 05-06Z and persisting into late Tuesday morning. HREF probabilities of ceilings below 3,000 feet show these sites on the southern edge of the highest chances, and periods of VFR conditions would not be unexpected. Will include a TEMPO period of lower ceilings there from about 09-12Z, before the arrival of low pressure and a more sustained period of sub-3K ceilings. Overall improvement is expected toward midday. Further south, VFR conditions expected to prevail from KSPI-KCMI as the front remains further north, though an overall lowering of ceilings to about 3500 feet or so is anticipated early Tuesday morning. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SYNOPSIS...Geelhart SHORT TERM...07 LONG TERM...07 AVIATION...Geelhart