Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/02/20

National Weather Service Albany NY
1054 PM EDT Wed Jul 1 2020 .SYNOPSIS... An upper low will slowly move east of New England tonight into Thursday. Temperatures will rise above normal on Thursday with just an isolated threat for an afternoon shower or thunderstorm into the early evening. A backdoor cold front will bring some showers and a chance of thunderstorms on Friday before mainly dry weather and slightly above normal temperatures for the holiday weekend. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... As of 1045 PM...The closed off upper level low over New England will move gradually eastward overnight. The convection has dissipate. Plenty of low-level moisture and a partial clearing will allow for patchy fog and low stratus to form again. A high amplitude ridge will be building in from the Upper Midwest, Great Lakes Region, and Central Plains. Lows will be in mid 50s to around 60F over the hills and mtns, and upper 50s to lower 60s in the valleys. The winds will become light to calm. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... Tomorrow...Finally, the closed H500 low will open and move off the New England Coast. Mid and upper level heights begin building in from west to east due to the high amplitude ridge upstream. Forecast soundings look primarily capped through the day into the mid afternoon. H850 temps warm to +17C to +18C based on the latest 12Z GFS. These are about +1 to +2 STDEVs above normal based on the latest 12Z GEFS. PWATs also increase to +1 to +2 STDEVs with a slightly more humid air mass building in from the south and west. Temps should rise above normal, and be about 10 degrees above normal. 12Z HREFs indicate mean SBCAPEs of 750-1500 J/kg over the forecast area with the 0-6 km shear about 20-30 kts. If the cap is broken then some isolated showers or thunderstorms may occur. The convective mode looks like multicellular. The possibility for this looks better in the late pm over the extreme north/northwest zones, where a weak disturbance may approach late in the day, and this is why SPC has a Marginal Risk over the southern Adirondacks/Lake George Region. The latest 3-km HRRR and NAMnest support isolated coverage, but the coverage should be much less than the past two days. Max temps may reach the upper 80s to lower 90s in the valley areas and upper 70s to mid 80s over the higher terrain. Thu night... A back door cold front begins to approach from the St Lawrence River Valley and northern New England. Low and mid level heights begin to fall. A short-wave in the north to northwest flow will may focus a cluster of showers and thunderstorms that may move from southern Quebec/northern NY and VT into the southern Adirondacks, Lake George Saratoga Region in the very late afternoon into the early evening. SBCAPEs may still be in the 1000-1500 J/kg range with ample shear. We agree with the Marginal Risk being pushed back into the northern most zones concurring with the trends of the NAM/GFS/ECMWF/Ensembles. A isolated severe thunderstorms with strong winds or marginal hail may be possible, and this cluster or MCS should be in a decaying stage. The threat should diminish shortly before or just after midnight. Lows will be milder and on the muggy side with mid and upper 60s in the valley locations and upper 50s to lower 60s over the mtns. Fri-Fri Night...The placement of the backdoor cold front will be critical for the degree of convection and the amount of rainfall on Friday. Also, the amount of heating/cloud cover will determine degree of instability. The 12Z NAM has the highest MUCAPEs west of the Hudson River Valley in the 1000-1500+ J/kg range with the 12Z GFS having 1000-2000+J/kg from the Hudson River Valley or close to the eastern NY border westward. The 0-6 km shear increases to 30-35 kts. It is possible an MCS may form with the potential for some elevated convection. We are not outlooked right now for severe weather due to the uncertainties in the instability and boundary placement. A diffuse boundary and a short-wave in northwest flow should allow for a period of rainfall or showers and a chance of thunderstorms. PWATs remain 1-2+ STDEVs above normal. The ridging from the east/northeast should allow for cooler temps and a low-level north to northeast flow. Max temps were kept in he mid 70s over lower 80s over the higher terrain and across western New England, and mainly lower to mid 80s in the valleys. Stay tuned for the trend with the placement of the backdoor front. Temps may need to trend down across the area. The showers and thunderstorms should diminish prior to midnight. The diffuse boundary may shift well to the south/southwest of the region. Some locations may receive up to an inch of rainfall Fri-Fri night. Lows will be in the mid 50s to mid 60s. Some patchy fog may also form with the moist low-level north to northeast flow regime. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... The main forecast challenge here in the extended continues to be the trends or prospects for precipitation across the FA. Atmospheric blocking highlighted by a trough-ridge-trough sequence (Omega Block) has been quite the persistent feature seen for the past few weeks nationally. Sometime during the first half of the long term (Sat. night-Monday), there are signals amongst the global forecast models and their ensembles that the aforementioned Omega Block will begin to breakdown as the H500 flow pattern flattens some. Timing, degree, and longevity of the breakdown (particularly as it pertains to the evolution of the upper trough to our north across eastern Canada) still remains in question. With a strong 591 dam heat dome established over the southern half of the country, the jet stream will remain established near or along the U.S.-Canadian border. There remains quite a spread amongst forecast guidance in the handling of mid-upper energy/shortwaves ejecting from an upper low across the Pacific Northwest and tracking eastward along or near the U.S.-Canadian border associated with the upper jet. The EC/CMC members remain mostly dry throughout much of the period (with the exception of Wednesday). The GFS/GEFS continues to indicate chances for precipitation particularly on Monday and Wednesday. Have included 30% chance pops for both Monday and Wednesday afternoon/evening using a blended approach. Capping will play a major role here. With geo-potential heights building over the FA in light of the expanding heat dome to the south, temperatures across eastern New York and western New England are progged to run above average (warm trending very warm/hot) during this period. So with that said, it appears that we could be entering a period of mainly drier conditions with warm to hot temperatures returning (perhaps with nearby MCVs passing to our north/west), punctuated by low chance pops for diurnally-driven showers and thunderstorms here and there (best days being Monday and Wednesday). Daytime high temperatures are expected to run from the mid 80s to around 90F degrees. Nighttime lows are expected to be mainly in the 60s (50s higher elevations). && .AVIATION /03Z THURSDAY THROUGH MONDAY/... The closed off upper level low over New England will move gradually eastward overnight and Thursday with ridging building in from the Great Lakes Region. The convection is not as robust as earlier and the coverage is decreasing with loss of diurnal heating. These trends will continue this evening. Plenty of low-level moisture and a partial clearing will allow for patchy fog and low stratus to form again with MVFR and IFR conditions expected. Conditions are expected to improve VFR by mid morning. Coverage of convection is expected to only be isolated Thursday so no mention in TAFs. Winds becoming calm tonight with a light northwest to north flow develop Thursday. Outlook... Thursday Night: Low Operational Impact. NO SIG WX. Friday: Moderate Operational Impact. Chance of SHRA...TSRA. Friday Night: Low Operational Impact. Chance of SHRA...TSRA. Independence Day: Low Operational Impact. NO SIG WX. Saturday Night: No Operational Impact. NO SIG WX. Sunday: Low Operational Impact. Slight Chance of SHRA...TSRA. Sunday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Monday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... An upper low will slowly move east of New England tonight into tomorrow with isolated to scattered showers and thunderstorms ending. Temperatures will rise above normal on Thursday with just an isolated threat for an afternoon shower or thunderstorm into the early evening. A backdoor cold front will bring some showers and a chance of thunderstorms on Friday before mainly dry weather for the holiday weekend. The RH values will increase to close to 100 percent for fog and dew formation Thursday morning. The RH values will lower to 40 to 55 percent Thursday afternoon, and then increase to 80 to 100 percent Friday morning. The winds will be light from the north at 5 mph or less tonight. The will be north to northwest at 5 to 10 mph on Thursday before become light Thursday night. && .HYDROLOGY... Widespread hydrological issues are not expected on the main stem rivers the next several days for the ALY Hydrological Service Area. Much of the HSA remains in either Abnormally Dry or Moderate Drought category per the latest US Drought Monitor issued last Thursday. Most rivers remain below the 25th percentile of 7-day average streamflow. Showers and scattered thunderstorms this afternoon into this evening will continue to bring locally heavy rainfall. The storms will be slow moving with potential for training, so locally heavy amounts of 1-2 inches are likely, which could result in minor urban/poor drainage flooding. An isolated flash flood is also possible. However, basin-average values are expected to be 0.10-0.75" inches over most areas. Very warm and mainly dry weather is expected tomorrow, isolated showers and thunderstorms cannot be ruled out especially over the higher terrain. Additional rainfall is expected on late Thursday night into Friday with a back door cold front. Some locally heavy rainfall is possible from any thunderstorms on Friday. Basin average rainfall my range from a few tenths to up to an inch. Drier weather is expected on the holiday weekend. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...IAA/Wasula NEAR TERM...IAA/Wasula SHORT TERM...Wasula LONG TERM...Evbuoma AVIATION...IAA FIRE WEATHER...Wasula HYDROLOGY...Thompson/Wasula
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
555 PM MDT Wed Jul 1 2020 .AVIATION..00Z UPDATE...SCT-BKN mid to high level clouds move north through the afternoon and overnight. A few -SHRA possible close to the border, but only have VCSH at KDMN for now as dry sfc air should limit rainfall reaching the ground. Storms will mainly be focused south of the international border, but outflows may attempt to race north and impact KDMN, KLRU and possible KELP with breezy to gusty winds ~00-03Z. If gusty outflow does develop, BLDU will be possible. Light VCSH will continue into morning hours, with possible VTCS in the evening especially at KTCS, KDMN, and KLRU. && 31 .PREV DISCUSSION...237 PM MDT Wed Jul 1 2020... .SYNOPSIS... Showers and thunderstorms will be more common in the forecast as the weather pattern aloft displays the typical monsoon flow expected this time of the year. Convection is expected pretty much everyday of this week, although the best chances are for the mountain areas. Strong outflow winds are possible with this activity which could also lead to blowing dust. Temperatures will be generally a few degrees above average, with mid to upper 90s expected in the lowlands. && 29 .DISCUSSION... .SHORT TERM... Current satellite shows a band of mid/upper clouds moving north with a few embedded showers (mainly south of Deming ~19Z) and perhaps virga most other areas. {There is/was a gravity wave out towards Guadalupe pass as well if you`re looking for something neat}. Additionally, a mix of clearing and broken clouds resides south of the border. All of this activity will continue to move northward through the evening and overnight hours. Iso showers will be the main threat although the HRRR model shows an outflow from supposed convection in northern Mexico pushing into the Borderland during the evening to early overnight hours. For what it is worth, convection across northern Chihuahua at this time (19Z) is less than impressive, and not as robust as the HRRR model suggests. Nevertheless, there have been instances as of recent with scattered showers in northern Chihuahua which produced outflow boundaries with dust. So, although confidence is relatively low (as HRRR seems to be the outlier), the possibility will still have to be monitored (taking a quick look at SPC`s meso page shows <1000 J/kg of DCAPE in northern Mexico as well, further adding a little suspicion). MLCAPE this afternoon and into the overnight will be minuscule so much of the activity that does progress northward/develop will be in the form of rain showers, but I guess a rumble or two or thunder will be possible early. Going into Thursday, moisture/dewpoints will remain sufficient across the CWA (mid to upper 40s most locations) so sct mtn thunderstorms expected with iso lowland storms. Lightning, brief heavy rain, and gusty winds will be the threats with the strongest storms. And of course, will have to watch for breezy outflow boundaries. High temperatures will be in the mid 90s most locations. && 35 .LONG TERM... Bottom line up front, an area of high pressure is expected to dominate through the long term period, but moisture will intrude in the lower levels bringing chances for showers and thunderstorms through the end of the forecast period. The main hazard with any storm that develops will be strong outflow winds, as deep dewpoint depressions persist. Some outflows may also lead to blowing dust. Temperatures will be generally a few degrees above normal through the week between the mid and upper 90s in the lowlands. Towards the end of this week, the chances for showers and thunderstorms increase as precip water values go up to around one inch; surface dew points rise into the 40s, and even to the 50s over Hudspeth County. A southeasterly flow keeps advecting the moisture into the region. Thus, we got the fuel to get storms, now we re missing the other two main ingredients. Instability is the complicated factor with this scenario, as the GFS shows marginal instability with MUCAPES generally below 500 J/kg, and LIs are around -1 to -2C, meanwhile the NAM doubles those amounts. However, seeing that an area of high pressure develops over the area on Friday, this should try to suppress the intensity of storms. The last ingredient lift is mostly provided by the mountains, and some convergence near the AZ/NM border. But it looks like the mountains will be the primary factor lifting the storms. Saturday evening appears to be the most active day through the weekend. Next week, the upper high centers over the Desert Southwest. This will inhibit storm development. Area mountains will have the greatest chances for storms, and the POPs are still low at the moment. By midweek, the upper high moves into the Central Plains and pretty much sets the pattern that we expect for the monsoon season. && 29 .FIRE WEATHER... Monsoon ridge develops across the region through the extended. As a result, moisture will increase, and outside of t-storms, winds will be mainly light to mildly breezy most days. Consequently, min RH will be mainly above 15% across the lowlands and 20-40% across area mountains. Saturday looks to the most active thunderstorm day, but starting Thursday, iso to sct mountain storms and iso lowland storms will be possible each afternoon. Ventilation will be a mix of Poor to Good most days with an increase possible on Sunday, and Haines index of 3-4. High temperatures will be near average through the weekend. && 35 && .PRELIMINARY POINT TEMPS/POPS... El Paso 74 96 74 98 / 20 10 10 10 Sierra Blanca 67 91 67 91 / 20 20 20 40 Las Cruces 69 94 68 96 / 20 20 10 10 Alamogordo 69 96 68 97 / 10 20 10 30 Cloudcroft 51 72 52 73 / 10 30 20 40 Truth or Consequences 69 93 68 95 / 10 20 10 20 Silver City 62 87 62 89 / 10 30 10 20 Deming 65 95 63 98 / 20 20 10 0 Lordsburg 65 93 64 96 / 10 20 0 10 West El Paso Metro 74 97 74 98 / 20 10 10 10 Dell City 69 98 68 98 / 10 20 20 30 Fort Hancock 71 98 71 98 / 20 20 20 30 Loma Linda 71 90 70 91 / 20 20 20 30 Fabens 73 96 73 98 / 20 20 20 20 Santa Teresa 70 96 69 97 / 20 10 10 10 White Sands HQ 74 95 73 96 / 10 20 10 20 Jornada Range 65 94 67 96 / 10 20 10 20 Hatch 66 95 66 97 / 10 20 10 20 Columbus 66 95 68 98 / 20 20 10 0 Orogrande 70 95 70 96 / 10 20 10 20 Mayhill 57 83 57 83 / 10 30 20 40 Mescalero 53 83 55 84 / 10 30 20 40 Timberon 53 81 53 81 / 10 30 20 40 Winston 49 86 54 88 / 10 40 10 30 Hillsboro 61 93 61 95 / 10 30 10 20 Spaceport 65 93 64 95 / 10 20 10 20 Lake Roberts 53 87 55 89 / 10 40 10 20 Hurley 59 90 59 92 / 10 30 10 20 Cliff 55 93 54 96 / 10 30 0 20 Mule Creek 56 89 62 91 / 10 30 0 20 Faywood 61 90 61 93 / 10 30 10 20 Animas 65 93 63 96 / 20 20 10 10 Hachita 67 93 61 95 / 20 20 10 10 Antelope Wells 63 92 63 95 / 20 30 20 20 Cloverdale 62 87 63 90 / 20 30 10 20 && .EPZ WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$ 31-Dhuyvetter/99/99
Area Forecast Discussion
National Weather Service Goodland KS
554 PM MDT Wed Jul 1 2020 .SHORT TERM...(This evening through Thursday) Issued at 1222 PM MDT Wed Jul 1 2020 18Z Water Vapor Imagery and RAP analysis indicate broad WSW flow occurring across much of the plains with ridge axis over the Great Lakes extending to the south into the Gulf Coast. At the surface, low was centered near KP28, with rich moisture advecting back into the CWA from the east with dewpoints already rising to the mid 60s near Hill City. Initial concerns will continue to be whether or not thunderstorms can initiate as deep moisture advects into the area. The increase in moisture yielding high ML CAPE values of 2000-4000 j/kg and little inhibition (< 10 j/kg). Only thing lacking is a forcing mechanism to lift parcels to LFC. Some hint at organized convergence late in the afternoon and given weak capping, that may be enough to spark a storm or two but confidence is low. If storms can develop, strong instability and strong directional shear will would support a threat for severe weather, but this threat remains conditional on storm initiation. As inhibition increases after sunset any storms that form should die off quickly with dry weather expected the rest of the night. Higher dewpoints will continue to move west across the area overnight, with dewpoints in the 60s getting to the western portion of the CWA by morning. This increased moisture, along with generally easterly flow will result in fog and stratus by sunrise. Magnitude of fog is uncertain as wind profiles would tend to favor stratus over fog, but expect a few areas of reduced visibilities. On Thursday, uncertainty somewhat high as morning stratus deck will play a large role in both the temperature and precipitation forecast. Right now, expect clouds to thin out similar to today and temps to warm into the mid 90s, with a few areas seeing the heat index near 100. Operational models all breaking out another round of thunderstorms by the afternoon, moving northeast across the area. Does appear to be shortwave trough embedded in the flow per dynamic tropopause maps, but not sure if stronger capping will overcome by such a subtle feature. Calibrated precipitation data also painting a much drier picture than the raw operational data. For now, not ready to buy into a widespread area of thunderstorms given capping, but do feel increasing forecast into the mid chance range warranted. .LONG TERM...(Friday through Wednesday) Issued at 219 PM MDT Wed Jul 1 2020 For the the 4th of July weekend, the models are showing an upper- level ridge dominating most of the regions east of the Rockies. There is mid-level moisture that the models are showing on the western half of the ridge. Combine this with the anticipated highs in the lower to middle 90s over the weekend, could produce afternoon/evening showers and thunderstorms over the Tri-State area. For the start of the work week the ridge axis become more of a northeast/southwest orientation extending from the Great Lakes region across the Texas Panhandle and into northern Mexico. This will produce a SW/W flow aloft over the local area. Temperatures will remain above normal with the highs reaching close to the 100 degrees mark by mid-week. The models do show an increase in shortwave troughs moving within this upper-level flow, which could lead to chance of showers and thunderstorms each afternoon/evening for the rest of the period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 521 PM MDT Wed Jul 1 2020 Low Level moisture increases overnight across the region with east winds turning southeast bringing dewpoints well into the 60s across the area. As a result, expect some low level clouds to develop around sunrise and continue for at least several hours into the morning with isolated to scattered thunderstorms developing Thursday afternoon and continuing into the evening. GLD will transition from VFR to MVFR due to lower ceilings between 11-15Z. VFR conditions will return after 15Z with a few thunderstorm possible after 22Z. MCK will go from VFR to MVFR conditions between 12-15Z and return to VFR conditions by 15Z. Thunderstorms will be lower in coverage and later in the day, possibly after 00Z Thursday evening, so have left those out of the TAF for now. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JRM LONG TERM...BW AVIATION...LOCKHART
Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
1003 PM CDT Wed Jul 1 2020 .SHORT TERM...(This evening through Thursday night) Issued at 250 PM CDT Wed Jul 1 2020 Dominate feature during the short term period will be building heights. These building heights will result in warming mid level temps, weaker mid-level lapse rates, less instability, stronger capping and much less convection than what we have seen the last few days. Today, mesoanalysis shows around 2000 j/kg of uncapped mlCAPE over western WI. This area will be susceptible to isolated shower development, though the HRRR and HopWRFs have been slowly backing away from coverage of thunderstorms today, so have confined pops to western WI and reduced them to 30s or less. There`s no shear out there today, so severe storms are no expected. Tonight, the concern comes from the fact we`ll have a baggy pressure pattern resulting in light winds. Add in clear skies, dewpoints around 70, and wet soils from recent rains and you have the potential for developing some patchy fog. HREF is pretty aggressive with creating fog/stratus in northern MN this evening, that builds down into the northern half or so of our CWA through the night. For this reason, added some patchy fog to the grids for tonight, basing the area mentioned on the visibility forecast from consshort. Thursday looks to feature even less cloud cover and a lower chance for rain. Did leave a slight chance for afternoon storms in WI, where many models develop some light QPF with a pool of slightly higher instability, though the vast majority folks will remain dry. With more sunshine, temperatures will be a couple of degrees warmer tomorrow and will send afternoon heat indices into the mid 90s, getting us into the area where there is a possibility of needing a heat advisory in the metro, but that looks borderline right now. .LONG TERM...(Friday through Wednesday) Issued at 250 PM CDT Wed Jul 1 2020 All we can say about the long term is that we are locked into a hot and humid weather pattern that looks to be going absolutely nowhere through the middle of July. It doesn`t look like we have any crazy heat on the way, it`s just solid summer warmth, with day after day of highs around 90 and dewpoints near 70, with the only possibility of reprieve being brief jaunts down to highs in the mid 80s. This is a low confidence setup for precipitation chances, but we will be near the northern edge of upper ridging, so we should have plenty of opportunities for seeing thunderstorms develop within the moist/unstable environment across the northern CONUS. However, with the subtle forcing features for thunderstorms and the fact that storms one day will often be influenced by what happened with storms the previous day, you end up with what the NBM gave us, PoPs that are basically climatology for Saturday night through Wednesday next week. Given forecast temperatures/dewpoints, we`ll also see day after day of afternoon heat indices in the 90-100 degree range. So pretty much every day will be near the threshold for needing heat advisories. In addition, this forecast has lows at MSP remaining 70 degrees or warmer every morning. The low this morning was 73, which would make this the second day in a row of not dropping below 70 so long as something unexpected doesn`t happen before midnight. If we go all the way to next Wednesday without going below 70, that would push the streak out to 9 days. The record for consecutive days of staying 70 or warmer was 11 back in July-Aug of 1935. This will be something to keep an eye on, though if we ever see good thunderstorm activity one day, the rain cooled air would likely send lows below 70 in the Twin Cities. For precipitation chances, they pickup Saturday night. On Saturday, thunderstorms will develop across NoDak within a very unstable environment ahead of a weak boundary. QPF forecasts from deterministic models continue to indicate a complex developing out of this that dives southeast toward central MN. Sunday precip chances will be tied to where any surface boundaries and MCVs end up from the Saturday activity. Next week is still looking potentially more active as the ridge flattens out and the northern stream dips back south. This pattern looks to hold until the end of next week, when a central CONUS ridge looks to build again. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) Issued at 1003 PM CDT Wed Jul 1 2020 High clouds will decrease a bit later this evening and winds will decouple. Areas of fog are expected to develop overnight, with the most widespread and dense over central MN. KMSP...Brief/patchy light fog is possible toward dawn Thursday morning, otherwise no concerns. /OUTLOOK FOR KMSP/ Fri...VFR. Wind SE 5 kts. Sat...VFR. Wind SSW 5 kts. Sun...VFR. Chc TSRA. Wind SW 5 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. && $$ SHORT TERM...MPG LONG TERM...MPG AVIATION...Borghoff
Area Forecast Discussion
National Weather Service Nashville TN
845 PM CDT Wed Jul 1 2020 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... Nearly all of the earlier convection has dissipated across Middle Tennessee and the reliable HRRR shows only a few cells occurring sporadically overnight, so have reduced POP`s across the mid state for the remainder of tonight and have also added some fog to the forecast through early tomorrow morning owing to the wet ground, light winds, and nearly saturated boundary layer. No other changes are planned for now. && .AVIATION... 00Z TAF DISCUSSION. Rains/storms are petering out this hour, leaving us with mainly VFR conditions across Middle TN. Problem is, it won`t stay this way. Look for poor flying conditions after 06Z as low cigs and vis settle into the area. IFR to LIFR can be expected through 14Z/Thu. Winds will be calm overnight, light and mainly easterly Thursday. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......08 AVIATION........Unger
Area Forecast Discussion...UPDATED
National Weather Service Springfield MO
919 PM CDT Wed Jul 1 2020 .MESOSCALE DISCUSSION... Issued at 855 PM CDT Wed Jul 1 2020 Mid evening temperatures were still quite mild and humid across southeast Kansas and western Missouri. There is a decent temperature, dewpoint and instability gradient across the area right now with dewpoints in the middle to upper 70s across the western half of the area along with MU capes of 5000-6000 (SGF 00z sounding measured 3000j/kg). Needless to say the atmosphere is highly unstable, especially for elevated parcels given that the airmass is largely capped at 800mb. Expectations for the overnight hours are for scattered to perhaps numerous showers and thunderstorms to develop in a northwest to southeast zone from roughly Nevada to Springfield to Eminence (give or take) largely after midnight. This is the time where the RAP eliminates CIN (cap) from elevated parcels (800-900mb). A remaining outflow boundary from southeast Kansas into Western Missouri may also be a trigger for storms. Therefore storms will be elevated in nature. Last few runs of the HRRR, NAM and RAP all show this activity developing and moving south to southeast during the early morning hours Thursday, therefore we will be increasing precip chances overnight. While wind shear will remain weak (25kts at best), the large reservoir of CAPE and steep lapse rates may allow for a few storms to become severe with large hail to quarters and winds to 60 mph possible. This matches the SPC marginal severe risk well. Frequent lightning also will be a concern. Locally heavy rainfall is possible but most locations can take some water right now. This activity may fester into the mid morning before weakening. The Heat Advisory remains in effect for tomorrow afternoon across southeast Kansas and western Missouri where heat index values will once again reach 105. Lastly, here are a few of the highest heat index values from today: 108F Fort Scott Kansas 106F Pittsburg, Kansas 103F Joplin, Missouri 100F Monett, Missouri 88F Springfield, Missouri (Had to throw that one in there... Clouds saved many locations from Springfield and points east) && .SHORT TERM...(This evening through Thursday) Issued at 257 PM CDT Wed Jul 1 2020 Remnants of the MCS still producing some rain over our south central counties this afternoon. These should exit by late this afternoon. After that, only isolated to scattered convection will remain possible the remainder of the afternoon and evening. Some of the CAMs are showing isolated to scattered storms tonight along the remaining outflow boundaries. Have thus kept in lower end probabilities through the overnight hours. The MCS did keep temperatures down on the eastern side of the heat advisory area. Thus will trim this back to just the western 2 tier of counties through 8 pm this evening. Another hot day is in store for Thursday with the upper level ridge in place overhead. With a moist airmass in place will likely see again mainly diurnally driven convection. Could see a few stronger storms given the moist environment and SPC has much of the area in a marginal risk. Temperatures will once again reach into the low to mid 90s, with heat indices in the 95 to 106 range. Will go ahead and issue a heat advisory for the western two tier of counties for Thursday afternoon and early evening. .LONG TERM...(Thursday Night through Wednesday) Issued at 257 PM CDT Wed Jul 1 2020 Hot and humid conditions will continue into Thursday evening along with the potential for isolated storms. Look for lows in the upper 60s to mid 70s. Will likely see more scattered convection continue into Friday, but will be less likely heading into Saturday and Sunday as moisture levels decrease. Highs will be slightly cooler with readings from the upper 80s to low 90s as the ridge retreats back west for a time. But early next week, the ridge once again strengths over the area, with temperatures likely going back up into the 90s for highs. Still cant rule out isolated to scattered mainly diurnally driven convection each day through this period, but at this point nothing widespread is anticipated. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 621 PM CDT Wed Jul 1 2020 VFR conditions are expected at the TAF sites through the period. Mid and high level clouds will persist through most of the evening and overnight hours. There may be showers and storms that develop overnight, mainly after 06z, that could come near the sites however confidence is not high enough to go any more than VCTS at this time. Winds will remain light and variable this evening. Winds on Thursday will start southerly and then turn to a northerly direction by afternoon. Additional showers and storms might return by the end of the TAF period. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...Heat Advisory from 1 PM to 8 PM CDT Thursday for MOZ066-077-088- 093-101. KS...Heat Advisory from 1 PM to 8 PM CDT Thursday for KSZ073-097-101. && $$ MESOSCALE...Burchfield SHORT TERM...Raberding LONG TERM...Raberding AVIATION...Burchfield