Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/30/19


AREA FORECAST DISCUSSION
National Weather Service Albany NY
954 PM EDT Sat Jun 29 2019 .SYNOPSIS... A cold front and potent upper level disturbance will bring scattered showers and thunderstorms to the region late tonight into Sunday along with cooler temperatures and breezy winds. Some storm may produce small hail. Less humid and seasonably warm conditions will return for Monday. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Updated at 10 pm. Storms have weakened across northern NY and no severe weather is expected from those showers as they work their way south across the Adirondacks overnight. Showers may reach the upper Hudson Valley and southern Green Mountains well after midnight as a strong short wave digs southeast from southern Quebec toward eastern NY and western New England. Farther south, a mostly clear and warm night will continue with lows settling into the 60s. Previous discussion is below. Updated at 8 pm. Storms have moved out of the southeast part of the forecast this evening. We are now watching an area of showers and thunderstorms moving across far northern NY associated with an unseasonably strong upper level trough digging southeast from Quebec toward New England. A few warnings have been issued on these storms for areas near the Canadian border, however we do expect some weakening with the sunset during the next couple of hours. Showers and thunderstorms will become likely over the southern Adirondacks late this evening through the overnight but we believe that the severe risk will be minimal by the time they get into our forecast area. Meanwhile, we are looking at a mostly clear, warm night for areas from I-90 southward, with increasing clouds after midnight from Albany northward. Previous discussion is below. Marginal to Slight Risk for Severe Thunderstorms through sunset today. GOES16 water vapor imagery shows a weak trough sliding southeastward through the mid-Atlantic with plenty of dry air in its wake with a few shortwaves pushing to our south through PA. Visible satellite combined with 20Z surface observations show a wind shift boundary positioned inbetween ALB and POU southwestward towards the Southern Tier. The air mass south of this boundary shows is very moist with dew points in the mid to upper 60s with SPC mesoanalysis showing SBCAPE values over 2000J/kg through the mid-Hudson Valley, Catskills into western New England. While the thermodynamics are impressive, shear is rather weak with effective shear values only 25-35kts in this area. As this boundary pushes through the buoyant sector positioned across our southern zones, it is sparking a few thunderstorms but so far none have been impressive. This is likely due to very weak mid-level lapse rates less than 6C/km combined with weak forcing for ascent and limited storm residence time within the buoyant sector. We will continue monitoring storms through 23z as an isolated or two strong to severe storm cannot be ruled out with gusty winds and large hail (mainly due to high instability values) being the main hazards. We lowered POPs from likely to chance through 23z in the latest update across the southern half of the forecast area to reflect latest thinking and the isolated to scattered storm coverage seen in radar/satellite trends. Once our wind shift boundary exits into southern New England/NYC towards 23/00z, there should be a break for dry weather as the dry air seen on GOES16 water vapor intrudes into eastern NY and western New England in the wake of the boundary. We thus gradually removed PoPs and decreased cloud coverage for the evening hours. Since this boundary is not introducing any real air mass change with winds only shifting from the southwest to the west-northwest, we should remain warm and muggy through the evening and overnight. Tonight our compact and potent shortwave trough continues digging southeast towards the US/Canadian border, leading to strong height falls over the Adirondacks into the Upper Hudson Valley. Latest RAP and high-res NAM show 500-1000J/kg SBCAPE lingering through 04z Sunday thanks to the long June days coincident with strengthening 0- 6km shear vectors between 30 and 40kts. Therefore, included potential for heavy rain and gusty winds from possible stronger thunderstorms in the Adirondacks and parts of the Upper Hudson Valley 00z to 04z Sunday. Coverage may be limited as the better forcing should be still north of our region but still wanted to include the potential for stronger storms this evening. Otherwise, we confined the highest POPs for showers and thunderstorms to areas well north and west of the Capital Region overnight where the best heights falls will ensue before gradually trending PoPs southward after 09z as our potent shortwave trough slides into the North Country. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... Very strong height falls and strong cyclonic vorticity advection will push southeastward through eastern NY and western New England on Sunday as an anomalous shortwave trough and its associated upper level cold pool impacts the Northeast. The shortwave`s 500 mb heights, as per the latest GEFS, are 2 to 3 standard deviations below normals which helps put the dynamics of this shortwave into perspective. Its associated trough axis should swing from north to south during the morning hours, reaching the Adirondacks, Upper Hudson Valley and Lake George/Saratoga region by 12z - 15z Sunday and pushing through the Capital Region into western New England and the mid-Hudson Valley from 15z to 18z. An initial area of showers and some thunderstorms can be expected with the trough axis/surface cold frontal passage with winds shifting from the west to the northwest. Our region will then be under the influence of the upper level cold pool from midday into the afternoon hours. With 500mb isotherms ranging -17C to -21C and WBZ heights under 10kft, we should see more convectively driven and scattered shower and storm coverage. We continued to mention the potential for small hail and gusty winds in any thunderstorms as well given this set-up. The latest guidance continues to place the steepest lapse rates of 6.5-7C/km east of the Hudson River into western New England so these regions should see more numerous shower/storm coverage. We also collaborated with SPC to expand the marginal risk for severe weather into this area. Such an environment also means any stronger updrafts can quickly lead to cloud to ground lightning so those with outdoor events or activities planned for Sunday should stay vigilant. Besides scattered showers and storms increasing in coverage underneath the cold pool tomorrow, winds should also turn breezy in the afternoon in the wake of the trough axis. Areas that receive more sunshine under the steep lapse rates should experience better mixing with gusts up to 25 to 30mph possible. Placed the highest gusts in the Catskills and Mohawk Valley which should see less shower/storm coverage than areas directly under the cold pool and thus better chance for some breaks of sun. Given how early in the day the trough axis passes through, northerly flow and cold air advection should occur through most of the day which will limit high temperatures to the mid to upper 70s in valley locations and 60s for those at 1000ft or higher. The Greens and northern Berkshires may end up being the coolest ranging from the 60s to lower 70s given greater storm/shower coverage and cloudier skies. The mid-Hudson Valley and NW CT should see some morning sun ahead of the approaching cold front so they have a better chance of nearing the 80 degree mark. Our shortwave trough should exit into New England by late afternoon with strong subsidence and height rises following quickly in its wake. We decreased POPs and cloud coverage quickly after 21z from west to east to illustrate the drying trend and clearing trend. Dew points will be falling through day under the northerly flow so those looking for less humid and cooler conditions can look forward to Sunday night. In fact, clear skies should help temperatures fall into the 50s (even 40s for the higher terrain). && .LONG TERM /MONDAY THROUGH SATURDAY/... Guidance is in good agreement regarding the longwave pattern for next week with a broad ridge across the CONUS with a low making gradually eastward progress across Canada. A short wave is expected to ride down the east side of the ridge bringing some showers to the area Monday night possibly into Tuesday. Fair weather is then expected through mid week as the ridge establishes itself over the region. Our next chances for convection are expected Thursday the 4th as a dampening short wave approaches and passes over the region. As we close out the week and heading into the weekend unsettled weather is expected as a cold front approaches and sweeps through in association with a short wave rotating about a large upper low as it moves eastward across Hudson Bay to Newfoundland/Labrador. Expecting seasonable temperatures to start July with highs in the mid 70s to lower 80s. Warmer, above normal readings, are expected for the remainder of the week with highs mainly in the 80s with some 90s possible as 850 mb temperatures to rise to near 20C, +1 to 2 standard deviations. In addition humidity levels are expected to noticeably increase. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... VFR conditions are expected at the TAF sites through this evening. Showers over the Adirondacks may get as far south as GFL after 06z with brief periods of MVFR conditions possible. A period of showers is likely at GFL and ALB Sunday morning, then scattered showers and thunderstorms can be expected at all of the TAF sites during the afternoon as a strong upper level system tracks from Quebec toward New England. Conditions through the day Sunday will be mainly VFR, except for briefly MVFR in scattered showers. The heaviest showers Sunday may contain a brief period of hail or gusty winds along with lightning. Winds will be light and variable tonight shifting to west- northwest at around 10 kts on Sunday with gusts of 15 to 20 kts during the afternoon. Outlook... Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: Moderate Operational Impact. Chance of SHRA. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Independence Day: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... Wind gusts up to 25 - 30 mph possible on Sunday... A strong upper level disturbance will bring isolated showers and thunderstorms to the region tonight before more widespread showers/storms arrive Sunday. RH values will range from 55 to 75 Sunday afternoon before turning lower on Monday, ranging from 45 to 55 percent. RH values both tonight and Sunday night should range 85 to 100 percent. Strong winds are expected on Sunday with westerly winds shifting to the north-northwest during the day and becoming sustained between 10 and 15mph with gusts up to 25-30mph possible. Northwest winds should weaken after sunset ranging 5 to 12mph through midnight before decreasing further by sunrise. Winds will be stronger and variable in direction in and near any thunderstorms. && .HYDROLOGY... Showers and thunderstorms and thunderstorms will drop southward across the Adirondacks tonight but rainfall should not be heavy enough to cause any signifcant flooding. Farther south, expect a dry warm night tonight. More widespread coverage of showers and thunderstorms are expected Sunday with locally heavy downpours possible but again, any flooding should be reserved to brief urban/poor drainage flooding. Areas east of the Hudson River into western New England should see the most shower/storm coverage. Drier weather is expected Monday before chances for showers return Monday night. Please visit our Advanced Hydrologic Prediction Service /AHPS/ web page for specific area rivers and lakes observations and forecasts. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Speciale NEAR TERM...MSE/Speciale SHORT TERM...Speciale LONG TERM...IAA AVIATION...IAA FIRE WEATHER...Speciale HYDROLOGY...Speciale
Area Forecast Discussion
National Weather Service La Crosse WI
648 PM CDT Sat Jun 29 2019 .SHORT TERM...(This evening through Sunday) Issued at 248 PM CDT Sat Jun 29 2019 Several concerns with how the convective trends are going to play out through Sunday leading to a low confidence forecast in the near term. Still watching the remains of the overnight convective complex over northwest Minnesota that none of the hi-res meso-scale models handled well and all would suggest should no longer be occurring. The RAP has been consistent taking the MCV from this complex southeast across northern and eastern Wisconsin overnight and if this complex can survive through the afternoon, it could ride along the edge of the MU CAPE gradient and come across the area north of Interstate 94. However, there has been a recent decrease in the lightning and some cloud top warming, so confidence in the complex making into the area is very low. Another complex, or two, should develop over North Dakota and then ride along the edge of the upper level ridge axis/CAPE gradient overnight. All the meso-scale models show this scenario, but have much different evolutions and timing. Some would bring the remains of a complex into the area before daybreak while others hold off until almost mid-morning. Most of the models would suggest the complex would mainly be over Wisconsin, but again, others bring it across the entire area. For now, have trended toward some activity coming in around daybreak or a bit later and moving across mainly Wisconsin. This complex also lends some doubt to how warm it will get Sunday. The heating will be delayed from the clouds and potential rain in the morning. However, subsidence behind the complex should allow for some clearing to occur during the peak heating and highs in the lower 90s still could be reached. With dew points well into the 70s, heat indices around 100 possible southwest of Interstate 94. It still may be necessary to issue a heat advisory for Sunday. Another round of convection will be possible late Sunday afternoon as a cold front moves across Minnesota. Abundant energy will be available ahead of the front with ML CAPE values of 4000 J/Kg shown by the RAP. Some capping will be in place ahead of the front but forecast sounding show this could be eroded by late afternoon. The shear does not look overly strong with 30 to 35 knots in the 0-3 km layer. Enough to support a risk for some severe storms with damaging winds being the main threat. .LONG TERM...(Sunday night through Saturday) Issued at 248 PM CDT Sat Jun 29 2019 On Sunday night, a cold front will move south into the region. The airmass will remain very unstable into the evening with ML CAPES of 4000 to 4500 J/kg. With 0-3 km shear up to 40 knots, the main threat will be damaging winds and maybe large hail. The main question is with a strong cap over the region how widespread the showers and storms will become and how far south will they get. The meso models currently suggest that convection will be either be ongoing or developing somewhere near the Interstate 90 corridor by early evening. However, this may change depending on where the boundary lays out on Sunday morning. With precipitable water values around 2 inches and warm cloud depths of 4-4.5 km, any showers and storms will very efficient rain makers. May need a Flash Flood Watch in areas where storms train. This front then looks to linger across the area through the work week. As waves move along this front, there will be periodic showers and storms. There is much uncertainty on the location and timing of these showers and storms. Afternoon and evening ML CAPES are in the 1500 to 3000 J/kg. The 0-3 km and 0-6 km shear appears to be weak for much of the weak. However, at times, they do increase as waves move through the region. During these times, there will be potential for severe storms. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 648 PM CDT Sat Jun 29 2019 Main aviation concerns are on the potential for Thunderstorms at the TAF sites Sunday morning with higher chances Sunday afternoon into Sunday evening. Thunderstorms will approach the region from the northwest late tonight into Sunday morning. However a strong CAP in place may keep this activity north of the TAF sites. A cold front slides in from the north by Sunday afternoon and we will likely see thunderstorms develop along the front and move south into the TAF sites, mainly after 21Z. Threats from the storms will include, damaging winds, large hail, heavy rain, and frequent lightning. && .HYDROLOGY...Sunday into Sunday night Issued at 648 PM CDT Sat Jun 29 2019 Precipitable water values of 2 inches and warm cloud depth of 4 to 4.5 km will set the stage for a heavy rain environment on Sunday. The first round of thunderstorms Sunday morning look to track north of Interstate 94, and will likely be weakening as they move into a cap. We should then see thunderstorms develop Sunday afternoon along an approaching frontal boundary. The storms will be capable of producing heavy rainfall and could be rather slow moving. Additional rounds of storms are possible Sunday evening into Sunday night. The high rainfall rates, and the potential for repeated rounds of storm raises the concern for flash flooding. 850 mb moisture transport becomes oriented parallel to the front Sunday evening so this could limit the heavy rain threat. However, with recent rains, soils are saturated in some areas and there are a few rivers already elevated or in flood. Will be issuing an ESF (Hydrologic Outlook) to cover the potential flooding threat and if confidence increases, a flash flood watch may be needed for Sunday afternoon into Sunday night. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...04 LONG TERM...Boyne AVIATION...Wetenkamp HYDROLOGY...Wetenkamp
Area Forecast Discussion
National Weather Service Bismarck ND
938 PM CDT Sat Jun 29 2019 .UPDATE... Issued at 938 PM CDT Sat Jun 29 2019 Trimmed the western four counties (Dunn, Stark, Hettinger and Adams) from the Tornado Watch. Several warnings issued earlier for cells in Stark and Morton counties, but most recent cell has weakened significantly as it moved through eastern Morton. Although quiet at the time, continuing to monitor southeastern parts of our area. Also adjusted pops to based on latest trends, mainly lowering pops. UPDATE Issued at 702 PM CDT Sat Jun 29 2019 Update to end the heat advisory. The impressive easterly/northeasterly outflow from the morning thunderstorms pretty much dominated the afternoon clouds, wind, temperature, and even dewpoint fields that were forecast. We had thought that the higher temps would eventually be realized by mid afternoon...but the temperature/humidity combination to make the heat index never came to fruition. UPDATE Issued at 610 PM CDT Sat Jun 29 2019 Update for tornado watch # 463 for parts of southwest and all of south central ND...mainly from Dunn/Adams counties eastward to Foster/Dickey counties...including Dickinson, Hettinger, Mandan, Bismarck, Fort Yates, Carrington, Jamestown, Oakes. && .SHORT TERM...(This evening through Sunday) Issued at 331 PM CDT Sat Jun 29 2019 Main forecast issues this afternoon and tonight will be thunderstorms and heat. The easterly winds and resultant cooler air from outflow from earlier thunderstorms has kept variable cloud cover over central North Dakota. Will take Stutsman County out of the heat advisory because of this. Because of the outflow from earlier storms, and latest mesoscale analysis from SPC indicates that even at 2 pm CDT there is still some CIN that is still squelching the potential surface-based cape of 2500-5000 J/kg. However, the potential is still there with MU CAPE above the mixed layer of 3000-5000 J/kg. Low level jet still remains in place, with the northern edge of the LLJ and surface warm front now in southern Manitoba. The surface cold front has been slow to enter western ND today, but extended from near Williston to just east of Beach and Bowman. Despite the cooler air moving in, the latest RAP sounding for Jamestown indicates a return of warmer air (90F) by around 00z, and increases low level southeasterly flow. The current mesoanalysis from Bismarck to Jamestown indicates an effective significant tornado parameter of 4-9. Bulk shear is perpendicular to the north- south cold front, so expect discrete cells to develop. Needless to say, plenty of available CAPE energy just above the surface, with higher dewpoints aloft as well with the LLJ, and plenty of effective shear remain. Large hail and damaging winds will be the main threat, as well as isolated tornadoes. Upper level impulses moving northeastward in the southwest flow aloft, along with convergence along the surface cold front advancing eastward into central ND will be the kicker for thunderstorms. Even now at mid-afternoon, upper level impulses are kicking off thunderstorms in northeast Montana/northwest ND/southeast Saskatchewan behind the cold front. Expect things to quiet down from west to east late tonight. Cooler and noticeably drier on Sunday with dewpoints in the 50s returning to our area. .LONG TERM...(Sunday night through Saturday) Issued at 331 PM CDT Sat Jun 29 2019 We return to more of a quasi-zonal flow through the remainder of the long term period. So not quite the heat and humidity, but the threat of thunderstorms will remain daily/nightly in the forecast. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 702 PM CDT Sat Jun 29 2019 Thunderstorms are expected to develop over parts of central and western North Dakota - with best chances at KDIK until around 03z...at KBIS and KMOT until around 05z...and at KJMS until around 07z. Severe storms are possible with large hail, damaging winds, lightning, and possible tornadoes through 06z, especially at KDIK, KBIS, and KJMS. The cold front at 00z extended from east of Stanley to just east of KDIK to east of KHEI. The cold front will push east this evening, reaching KJMS by 05z-07z. Southeast winds ahead of the front and northwest winds behind it. VFR conditions later tonight and all day Sunday. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JNS SHORT TERM...JV LONG TERM...JV AVIATION...JV
Area Forecast Discussion
National Weather Service Quad Cities IA IL
644 PM CDT Sat Jun 29 2019 ...00z AVIATION UPDATE... .SYNOPSIS... Issued at 329 PM CDT Sat Jun 29 2019 At 230 PM a hot and humid airmass is in place across eastern Iowa, northeast Missouri, and parts of northwest Illinois. Dew points ranged from the upper 60s in Freeport to the upper 70s at Fort Madison, Keokuk, and Fairfield. This was producing heat indices of 99 to 105 in south of a line from KMXO to KCWI to KVYS. A frontal boundary stretched from Waterloo to Monticello to Clinton to KVYS. Scattered showers and storms were beginning to develop along a Davenport to Princeton Illinois line. && .SHORT TERM...(This Evening through Sunday) ISSUED AT 329 PM CDT Sat Jun 29 2019 My main forecast concerns are temperatures and chances of precipitation. Models are in good overall agreement but big differences between the synoptic and convective allowing models over the next 24 hours. Isolated showers and thunderstorms are possible late this afternoon into this evening with convergence along a pseudo frontal boundary across the region. There is a 10 degree dewpoint drop across the front. This may help to focus thunderstorm development late this afternoon. Risk of showers and thunderstorms will fall once the temperatures begin to cool. The HRRR shows convection lingering in this area between 2 and 3 UTC. Shear is weak and showers and storms will slowly drift across the area. Our focus then shifts to tonight. Synoptic models show a temperature and dewpoint gradient across the region they may lead to a Mesocale Convective System (MCS) tracking across the area Sunday morning. The 850 MCS track can be highlight by the 18 to 20C temperatures at this level which several synoptic models show across the area. This is also in the same area where models depict a strong CAPE gradient which in the MCS may want to ride However the 200mb divergence is farther to our north and east across Minnesota and Wisconsin which would say the better convection and storms would be to our northeast Sunday morning. The 4km NAM Nest develop an MCS tonight across Minnesota and depict it moving into our area Sunday morning but the HRRR on develops scattered convection overnight. The risk is then there for showers and storms Sunday morning and afternoon. The MCS potential has a huge impact on the forecast for temperatures and heat indices on Sunday. If an MCS develops and moves across our area that will limit warmer temperatures until later in the day . if there is no lingering thicker cloud cover from it. The current forecast has temperatures in the lower 90s with heat indices maximizing near 100 or 101. Both solutions are possible and for this reason there is not a heat advisory for Sunday. We will revisit this with later shifts. .LONG TERM...(Sunday Night through next Saturday) ISSUED AT 329 PM CDT Sat Jun 29 2019 Sunday night...In the wake of whatever convective system can make it down acrs the area earlier on Sunday, thermal ridge acrs the plains over to the GRT LKS will look to get dampened acrs the Dakotas and MN by passing ridge-riding short wave. The next round of MCS generation parameters come together acrs SD, the southern third of MN and into WI for renewed development of convective clusters Sunday evening. Of course being this close, some chance for a portion of this activity to bleed down into the northern or northeastern CWA late Sunday night into Monday morning. It will be battling the ongoing elevated mixed layer as it does and have trouble maintaining, or it could develop a cool pool with it`s own shear mechanics and move down into portions of the local CWA as a strong to severe storm complex with winds and heavy rain. This may be the same scenario for days to come living on the edge of the "ring-of- fire" pattern. Monday...As with many days in the bulk of the longer range period, much will depend on how much or if any of the CWA get`s impacted by a nocturnal MCS or storm clusters from the north, and then the associated lingering debris affecting how warm our area gets. With a lack of debris and enough daytime recovery, much of the area may near heat headline criteria again Monday afternoon. Then there will be again a nocturnal chance for storms especially in the north later Monday night into Tue morning. Enough high to extreme instability to the south for ringing storms on the edge of the heat dome to produce strong to damaging winds even with marginal shear profiles. Tuesday through next Saturday...Tuesday may be similar to Monday being hot and humid with nighttime storm chances, before signs of the continued ridge dampening may bring the storm track further south for a more direct line acrs the local area Wed into Friday. Rounds of moderate to heavy rainfall may start to add up acrs portions of the area mid to late week with some local river implications possible. Longer range signs suggest that maybe high pressure building south down acrs the Upper MS RVR Valley and GRT LKS may shunt the storm track or convective action zone to the south of the region from KS over to the OH RVR Valley from late Friday and through the next weekend. The pattern shift to bring about cooler temps as well. or at least to more seasonable levels later in this period. ..12.. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) ISSUED AT 635 PM CDT Sat Jun 29 2019 Widely scattered convection will continue through sunset before diminishing. CID and MLI would appear to be most susceptible and will continue to monitor radar trends and amend if needed. Some CAM guidance is suggesting potential for storms that form over the Dakotas tonight could move into the area tomorrow morning, while other guidance keeps this activity north. This uncertainty owes to low confidence and therefore have kept out any mention for now. Expect MVFR to IFR conditions in any convection, with VFR conditions generally otherwise. There is a chance of some patchy fog late tonight at MLI, which received some rain earlier. && .HYDROLOGY... Issued at 1215 PM CDT Sat Jun 29 2019 It still appears that an active weather pattern with an ongoing storm track acrs portions of the upper Midwest will last through the upcoming week. Latest indications suggest that the resultant rounds of heavy rain will most likley occur acrs areas to the north over southern MN, northern IA and WI. Some recent heavy rainfall has already fallen acrs portions of these areas during the past few days. This and additional rounds of rain will run-off and eventually make it into the upper basin of the Mississippi River system and flow southward. This will most likely produce eventual rises on the local stretch of the Mississippi during this coming first week of July. Currently most sites on the MS RVR are falling with Gladstone LD18 dropping below the flood stage today, and only two other sites remaining above flood stage. The exception is Dubuque down to Bellevue areas which are showing steady to slow rises already from recent rains upstream. This flow will continue to work on down and continue to produce rises at the other sites through the upcoming week. But with the recent downtrends along much of the local stretch of the Mississippi, most rises are projected to remain nominal and below the action stage. The exceptions may be at some of the southern sites that are still high such as Keithsburg, Gladstone LD18, Burlington, and Gregory Landing which are prevented from falling below the action stage from the additional flow routed through those sites. Some chance that Gladstone, Burlington and Gregory Landing may approach the flood stage again by late next weekend. Some of the tributary rivers with reaches further to the north will experience rises into next week as well from recent and projected heavy rainfall in those areas. Rivers such as the Cedar, Iowa, and Wapsi will experience rising trends, with a few sites making over the action stage or held up above action if already over that stage. The Wapsi at De Witt may rise to just under the flood stage by the 4th of July. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Heat Advisory until 9 PM CDT this evening for Benton-Buchanan- Cedar-Clinton-Delaware-Des Moines-Henry IA-Iowa-Jefferson- Johnson-Jones-Keokuk-Lee-Linn-Louisa-Muscatine-Scott-Van Buren-Washington. IL...Heat Advisory until 9 PM CDT this evening for Bureau-Hancock- Henderson-Henry IL-McDonough-Mercer-Putnam-Rock Island- Warren-Whiteside. MO...Heat Advisory until 9 PM CDT this evening for Clark-Scotland. && $$ SYNOPSIS...Cousins SHORT TERM...Cousins LONG TERM...12 AVIATION...McClure HYDROLOGY...12
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
659 PM CDT Sat Jun 29 2019 .AVIATION... /00Z TAFS/ Rapid refresh models depict the East TX convective activity beneath the shear axis aloft to enter into Central TX close to midnight. This matches up well with the latest radar trends showing echoes moving mainly south with outflow boundaries pushing west to trigger new convection. Winds could become gusty briefly with the leading edge, but the overnight timing should allow for the low level air to cool enough to limit the potential for strong wind gusts. The shear axis will still be rooted in East TX so it is unlikely the convection will remain deep as the instability propagates into the San Antonio area. Whats left for the forecast is a long period of vcsh as the skies should be chaotic and tropical in nature with cirrostratus probably being the most common cig. There could be brief mvfr episodes overnight into early Sunday but expecting high moisture content in the atmosphere to keep the air well mixed. Sometime in the midday hours Sunday, future TAF updates will need to consider periods of prevailing thunder as the shear axis becomes almost directly overhead. && .PREV DISCUSSION... /ISSUED 258 PM CDT Sat Jun 29 2019/ SHORT TERM (Tonight through Sunday Night)... Across the U.S. this afternoon we see a trough over the Pacific NW, upper ridging over the central Plains into the desert SW and an inverted trof over far east Texas. The trof over the eastern part of the state will be our main weather maker over the next several days, lingering into next week. The overall pattern will be unsettled over texas through much of the forecast so most periods will have mention of pop except for mainly the far west along the Rio Grande where most of the week will remain dry and rain free. The upper level low pressure area that has been moving west over the past few days has come into eastern Texas. Showers and storms are ongoing over the Houston area, extending north into east Texas. The latest runs of the HRRR and TXTech WRF show convection to the N and NE making its way into our northern counties by evening. I think we will have only minimal convection this afternoon, if any at all, as visible shows very weak cu formation. Have scaled back pops the rest of the day, but left them in over the far E and NE zones. Storms could approach this area by 00z and linger through the evening. The High resolution models take this activity and bring it through our northern CWA late this evening into overnight so have kept decent POP and scattered activity mentioned. We remain in the Marginal Risk from SPC...with mainly wind being the biggest threat. Temps will be fairly mild overnight. The upper low will be over the area on Sunday, with scattered convection possible anytime of day, morning and afternoon. Boundary driven storms and complexes could bring some isolated rain totals well over 1 inch but confidence is low on timing and exact location. Will likely be more clouds than sun on Sunday so look for afternoon temps mainly in the mid to upper 80s. If the storms come in early and leave some June sunshine...temp forecast will bust...cant rule out some lower 90s for this reason. Will keep a 30 pop ongoing through the eastern 2/3rds of the cwa Sunday Night. The west will remain mostly dry. LONG TERM (Monday through Saturday)... The overall pattern really doesnt change much for most of next week. The upper trof/low will linger over the state, get stretched a bit north to south and eventually moves NE and weakens. So best rain chances will remain the first half of the week with a moist atmosphere and lack of high pressure ridging. Scattered pops will be the result. As the influence of the upper low lessens by the 4th and then Friday, rain chances finally go down, clouds decrease, and temps near normal make a return. Low pressure over the Rockies mid week will also bring back a stronger southerly wind for us...so look for wind speeds to increase by mid week as well. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 71 87 70 88 71 / 50 50 30 30 10 Austin Bergstrom Intl Airport 70 86 70 88 70 / 50 50 30 30 10 New Braunfels Muni Airport 69 87 70 88 69 / 40 50 30 30 10 Burnet Muni Airport 70 87 68 87 68 / 40 50 30 30 10 Del Rio Intl Airport 72 93 72 93 72 / 10 10 10 - 10 Georgetown Muni Airport 70 87 69 88 69 / 50 50 30 30 10 Hondo Muni Airport 71 89 70 92 71 / 30 40 30 10 10 San Marcos Muni Airport 69 87 70 89 69 / 40 50 30 30 10 La Grange - Fayette Regional 72 87 71 89 71 / 50 50 20 30 10 San Antonio Intl Airport 71 88 71 89 71 / 30 50 30 10 10 Stinson Muni Airport 72 88 72 90 71 / 30 40 30 10 10 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Aviation...Oaks Short-Term/Long-Term...04 Public Service/Data Collection...33
Area Forecast Discussion
National Weather Service Fort Worth TX
740 PM CDT Sat Jun 29 2019 .AVIATION... /00Z TAFs/ Thunderstorms currently rolling through the Metroplex have become loosely organized along an outflow boundary arced in the shape of a half-circle between the Dallas area and Waco. Storms will continue to push southwest; exiting the DFW area while entering the Waco area in the next hour. Gusty winds will be the primary concern, though with dwindling surface heating, the severe threat should be on its way down. Easterly winds behind the outflow boundary should weaken later this evening and eventually turn to the southeast by sunrise Sunday. There is an outside chance of MVFR in the Dallas area early Sunday, so will maintain the TEMPO group for DFW and DAL for Sunday morning. For Sunday afternoon, there is an outside chance for a few storms, but activity will have shifted mainly south and west of the region along with the upper level disturbance responsible for this evening`s convection. 30 && .SHORT TERM... /Issued 228 PM CDT Sat Jun 29 2019/ /Through Sunday Morning/ The main challenge in the short term forecast period will be convective chances across the area. Surface analysis this afternoon revealed an outflow boundary was noted near a Bonham to Greenville to Nacogdoches line. This feature...coupled with a diffuse mid/upper level impulse will likely be the impetus for what should be a proliferation of shower and thunderstorm activity. Mesoanalysis indicates a very healthy instability profile with CAPE values in excess of 3500 J/kg. Recent AMDAR data out of Dallas Love Field indicates respectable north to northeasterly mid and upper level flow for late June and as a result...we could see some loosely organized convective modes that will generally travel from the northeast to southwest. Given the inverted-V type sounding profiles and 0-3km theta-e deficits of around 30K...we will have to contend with a damaging wind risk. Deep layer shear around 30 knots will support quasi- steady state updrafts and when coupled with the high to extreme instability will yield a large hail risk. Heavy rain and flooding will remain a threat, though storm motions should be sufficiently high to preclude a long duration heavy rain episode. Any training echoes, however, will be monitored for a brief flash flood risk. The 12 UTC NAM NEST appears a little too aggressive with its depiction of a well organized MCS by early evening. While I do feel that the potential exists for a a loose complex of storms, it still remains uncertain how expansive it will be. The current forecast continues to favor scenarios advertised by the latest HRRR and 12 UTC TTU WRF. The best potential for rain/storms will be near and east of a Killeen to Hillsboro to D/FW to Sherman/Denison line trough the evening hours (though rain/storm chances exist west of this line). Some nocturnal convection may persist tonight into Central Texas and I`ll hold onto a 40-50 PoP near and south of the I-14/US HWY 190 corridor through 12 UTC. If a well established MCS gets going, PoPs may need to be increased. There will be a potential for some morning stratus/fog north of I-20 and east of I-35, but confidence is a little too low to include in the forecast at this time. Bain && .LONG TERM... /Issued 228 PM CDT Sat Jun 29 2019/ /Sunday Through This Week/ We`ll continue to track out southwest-moving mid level disturbance across Southeast Texas into South-Central Texas during the day Sunday. Early in the day, expect most concentration of showers/ thunderstorms to be in close in vicinity of this immediate track with our far southern Texas counties seeing the best chances through early afternoon. Afterward, surface boundaries, differential heating, and pockets of instability along the edge of anvil debris has me introducing 20% PoP through the remainder of our CWA and to the Red River Valley. Though a strong storm can`t be ruled out farther north where better instability will likely reside from stronger insolation, Theta-E deficits in the surface to 700mb layer do not look near as pronounced as today, so the severe risk will be much less. High temperatures remain problematic and completely at the mercy of who breaks out of the clouds and who doesn`t. Central Texas areas may be hard- pressed to get into the mid 80s, while lower 90s are likely in the far northwest where more insolation is likely to be found Sunday afternoon. Low convective chances will remain Sunday night, mainly across Western Central Texas in vicinity of our system and better ascent, which will slowly pull away from our area on Monday. I can`t rule out isolated, more "airmass" type diurnal activity across the region on Monday, but for most folks the forecast will be seasonably very warm and humid with no additional rainfall. The lull in precipitation chances will continue Monday night into Tuesday morning, before increasing across Central Texas later Tuesday and Tuesday night, as a shortwave lifts northward from the Western Gulf of Mexico and across the Sabine River Valley. Embedded shortwave energy will continue within a "weakness" between two weak upper ridge axes moving into the mid week and 4th of July holiday period with mostly diurnally-driven shower and thunderstorm chances will continue across much of the area. I`ll stress with weak flow and subtle forcing aloft and no synoptic surface focusing mechanisms around, that this will NOT be a complete washout for outdoor activities and fireworks, as the loss of heating each evening should help diminish coverage and intensity of most convective activity after dark. Otherwise, a broad, but not overly intense subtropical upper high expands across the Southern CONUS for more typical Summer conditions next weekend and beyond. A few diurnal hit n` miss storms each afternoon and early evening, but nothing widespread. Highs will average in the lower- mid 90s. 05/ && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 72 89 71 90 72 / 30 20 20 20 5 Waco 70 87 70 89 69 / 50 30 30 20 10 Paris 69 87 69 88 70 / 30 20 20 20 5 Denton 71 89 70 90 71 / 20 20 20 20 5 McKinney 71 87 70 89 71 / 30 20 20 20 5 Dallas 73 90 72 90 72 / 30 20 20 20 5 Terrell 71 87 70 90 71 / 30 20 20 20 5 Corsicana 69 86 68 86 69 / 50 20 20 20 10 Temple 70 86 69 88 68 / 60 40 30 20 10 Mineral Wells 69 90 68 89 68 / 20 20 20 20 5 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 30/11
Area Forecast Discussion
National Weather Service Green Bay WI
700 PM CDT Sat Jun 29 2019 Updated aviation portion for 00Z TAF issuance .SHORT TERM...Tonight and Sunday Issued at 236 PM CDT Sat Jun 29 2019 The latest RAP analysis and satellite/radar imagery show a weak area of high pressure stretching from northwest Ontario and across the western Great Lakes early this afternoon. Low pressure resides over the western Dakotas, with an associated warm front extending southeast into southern Minnesota, and northern Iowa/Illinois. Residual low level moisture and daytime instability contributed to a cu field over central to northeast Wisconsin, while dewpoints mixed out into the upper 40s over Vilas county. Meanwhile, north of the warm front, a severe MCS is ongoing near the ND/MN border. As the warm front returns northeast into northeast WI late tonight into Sunday, forecast concerns mainly revolve around the potential for severe thunderstorms. Tonight...Fair weather cumulus clouds will dissipate early this evening, but should see an influx of cirrus from the west from the thunderstorm activity upstream. This should result in a mostly clear to partly cloudy evening. Additional mcs activity is forecast to develop over eastern North Dakota and northern Minnesota this evening, then track towards northwest WI by late in the night. If track and timing go according to plan, then should see increasing clouds overnight with storms approaching north-central WI by around 6 am. Lows tonight ranging from the middle 50s near the U.P. border to the middle 60s over the southern Fox Valley. Sunday...A thunderstorm complex is expected to track southeast along the warm front Sunday morning along the edge of the mid-level cap and across northwest and central WI. Track of this complex diverges in the higher resolution models by this time, but potential remains for strong to severe thunderstorm activity to impact central WI in the morning, where SPC has a slight risk. The main threat should be damaging winds and heavy rainfall, but if there is a later arrival, the storms could have a brief opportunity to interact with daytime instability of 2000 j/kg of cape. The latest guidance suggest that the threat of storms should end by around midday. Some concern that storms may redevelop in the afternoon along the warm front. But the atmosphere will need time to recover after the morning storms, and will have to overcome mid-level capping. Chances will therefore remain low. Some clearing is likely in the afternoon, which will help temps warm into the mid to upper 80s away from Lake Michigan. .LONG TERM...Sunday Night Through Saturday Issued at 236 PM CDT Sat Jun 29 2019 Precipitation trends and the potential for severe thunderstorms and heavy rainfall will be the main forecast concerns. Models suggest that convection will be focused in central WI Sunday evening, where low-level moisture convergence will occur north of a warm frontal boundary. PWATs are forecast to approach 2 inches in our southwest counties, so heavy rainfall will be a significant threat. CAPE is also expected to be in the 2000-3000 j/kg range during the evening, which will also support a severe threat, even though deep layer shear is fairly weak (20-25 kts). In the far north, a weak cold front may also trigger some storms Sunday night. Have focused likely pops in those two areas, with chance pops elsewhere. The weak cold front is expected to sag through the area on Monday, then lift back to the north as a warm front as low pressure tracks toward the forecast area late Monday night into Tuesday. The threat of heavy rainfall and severe weather should return as the low pressure system and warm front approach. Will carry likely POPs across part of the area Late Monday night into Tuesday, though the placement of the highest POPs and QPF may need to be adjusted as details come into focus. After the low shifts east, the front is expected to drop south of the region again Tuesday night into Wednesday night. This may result in a bit of a lull in the precipitation, though confidence is too low to go with a dry forecast. The front should return as a warm front again on Thursday, followed by a cold frontal passage Thursday night into Friday. Precipitation chances should again be maximized near these boundaries. Medium range models suggest that Canadian high pressure may drop into the western Great Lakes for the weekend, resulting in cooler, drier and less humid conditions. && .AVIATION...for 00Z TAF Issuance Issued at 659 PM CDT Sat Jun 29 2019 Generally VFR conditions through about 12 UTC Sunday with mainly remnant cirrus debris moving overhead this evening from dissipating convection earlier in the day over Minnesota. Attention will continue to focus on when and where upstream convection will fire over the Dakotas later this evening. How this convection evolves will determine daytime flying conditions over the forecast area on Sunday. Model guidance continues to be quite variable on location and movement of thunderstorm complex forecast to develop west of the Mississippi River overnight and track somewhere over the western Great Lakes by mid-morning Sunday. Latest model guidance appears to be slower in bringing thunderstorm complex into western portion of the forecast area Sunday morning. Bottom line is that forecast confidence on evolution of thunderstorm activity after 12 UTC Sunday is low, thus was more conservative on explicit mention of thunder in 00Z TAFs. Once convection develops over the Dakotas later this evening, will hopefully be able to add more specifics to location and timing to thunderstorm potential for upcoming 06Z TAF issuance. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......Kieckbusch AVIATION.......ESB
Area Forecast Discussion
National Weather Service Marquette MI
630 PM EDT Sat Jun 29 2019 .SHORT TERM...(This evening through Sunday) Issued at 411 PM EDT SAT JUN 29 2019 WV imagery and RAP analysis indicated a mid/upper level ridge from the Central Plains to Hudson Bay and a low just southeast of James Bay resulting in nw flow through the northern Great Lakes. At the surface, a ridge extended from northern Ontario through the western Great Lakes with a weak pressure gradient allowing prominent lake breezes to develop. The North Dakota MCS has fallen apart as it moved into northern MN leaving a large area of convective debris cirrus from MN into nw WI. Otherwise, mostly sunny skies prevailed through the region. Tonight into Sunday morning, Models suggest that another MCS will develop over ND or southern Manitoba where the low level jet is focused near the axis of maximum CAPE. The CAMs have been consistent in dropping this features southeast into WI while the NAM and regional GEM have been outliers in bringing shra/tsra into western Upper Michigan. While the MCS is most likely to track closer to the CAPE gradient into WI, cannot rule out some shra/tsra on the fringe of the MCS that may brush the west. Sunday afternoon, if the leftover clouds and convective debris clear out by mid afternoon, temps should quickly climb back into the mid 80s inland. The evolution of the morning convection will also result in uncertainty with the potential for redeveloping tsra in the afternoon as the sfc trough approaches. MLCAPE values into the 1k-2k J/Kg range will be possible that could support tsra development near lake breeze boundaries or if any weak shrtwvs approach. .LONG TERM...(Sunday night through Saturday) Issued at 347 PM EDT SAT JUN 29 2019 Rain/thunderstorm chances Sunday evening remain somewhat a mystery as they will depend on whether or not the NAM`s advertised MCS materializes. Have gone with chance POPs west and south at 00z to reflect either the MCS happening (but being delayed), or it not happening and therefore new convection firing out west before 00z a la the GFS. After that, the models (except the NAM) converge on resolving a frontal band of precip from about 06-12z across Upper Michigan so after that evening lull, bring POPs back up to high end chance/likely. But ultimately have to admit that there is not a lot of confidence in how things shake out Sunday night. Though this front is technically a cold front, the drop in temps will hardly be noticeable - 850 mb temps come down by about 2-3 C which means highs will still be in the 80s for most - but with dew points dropping from the mid 60s to low to mid 50s, Monday will at least feel a bit more comfortable with somewhat reduced humidity. It`s a short lived reprieve, however. Southwesterly low to mid level flow develops Monday evening and begins pumping moisture back northward into the area ahead of a developing low in Minnesota. What remains in question is just how far north the precip will get, with the EC and CMC keeping it just along or just south of the Wisconsin line while the American models drive it right through Upper Michigan to Lake Superior. For now, have just chance POPs south and slight chance north but look for those to come up in future packages. The system`s timing (the warm sector passing overhead Monday night and Tuesday morning) does not support severe weather. So while some elevated thunderstorms are certainly possible (best chances south), Monday night-Tuesday looks more like a hevay rain threat at the moment (should the American models verify) given strong moisture transport and PWAT rising to 1.5-1.8". Behind this system things dry out for Wednesday and thursday... but not completely. Quite a bit of model spread still in resolving subtle short waves so have stuck to the model blend with slight chance to chance POPs. Therefore, can`t rule out some showers/storms for the Fourth, but it doesn`t look like a washout at this point. GFS and EC agree that we finally break out of this hot pattern by the end of the week with a rather strong cold front either Friday or Saturday. That means a renewed chance of showers and storms as well, but not worth getting hung up on the details yet this far out. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 630 PM EDT SAT JUN 29 2019 Expect VFR conditions at all terminals through the entire forecast period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 411 PM EDT SAT JUN 29 2019 Patchy to areas of fog will be possible over eastern Lake Superior tonight. Winds of less than 20 knots can be expected through the forecast period. The next chance for thunderstorms arrives late tonight into early next week, with periodic chances persisting next week. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Dense Fog Advisory until 8 PM EDT this evening for LSZ251-266- 267. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...RJC AVIATION...07 MARINE...JLB
Area Forecast Discussion
National Weather Service Pueblo CO
317 PM MDT Sat Jun 29 2019 .SHORT TERM...(This evening through Sunday) Issued at 244 PM MDT Sat Jun 29 2019 Mainly isolated thunderstorms have again developed over the higher terrain this afternoon, as mid level moisture plume to our west continues to edge eastward into CO, with some subtle moistening of low levels as well. Max temps still running on the hot side many locations, with readings over 100f at Lamar and La Junta as of 3 pm. Storms will continue to percolate over the mountains into the evening, with some activity drifting out into the I-25 corridor after 00z, as HRRR shows a few modest cells along the ern mountain slopes until around 03z. Gusty winds and lightning remain the main storm threats, as cloud bases will stay rather high. Most showers/thunderstorms should then end by late evening, though a few weakening showers may linger toward midnight along the Continental Divide, as mid level moisture begins to increase. Plenty of convective debris cloudiness will linger across the entire area overnight, keeping min temps rather mild into Sun morning. On Sunday, upper pattern remains generally unchanged, with elongated ridge stretching from sw to ne across CO. Recycled moisture and a slow upturn in precipitable water under increasingly moist sw mid level flow will lead to more widespread convection across the mountains and interior valleys Sun afternoon, with most activity again staying along and west of I-25. Main threat will be lightning and wind, though potential for brief heavy rainfall on burn scars can`t be discounted. Clouds and increasing precip will hold back max temps slightly, especially mountains, though a few spots in the lower Arkansas Valley may again reach 100f. .LONG TERM...(Sunday night through Saturday) Issued at 244 PM MDT Sat Jun 29 2019 Not much change to the forecast thinking over the past 24 hours. The upper pattern will be dominated by high pressure, stretching from the Desert Southwest into the Central Plains with broad, weak southwesterly flow aloft across Colorado. Operational models are in good agreement and ensemble spreads remain low throughout much of the extended period. Sunday night into Tuesday...showers and thunderstorms will be ongoing over the higher terrain Sunday evening. Lack of steering flow should help keep storms from moving too much, which will likely lead to an elevated flash flood through over area burn scars through the evening hours. Expect this activity to dissipate with sunset and generally dry conditions expected to prevail into Monday morning across the region. By Monday, an upper disturbance is forecast to track across Colorado. This will help increase the southwesterly flow aloft which will aid in shifting showers and thunderstorms off the higher terrain and across the Plains through Monday evening. Locally heavy rainfall will be possible, and an elevated flash flood risk is possible on burn scars. As for severe weather, wind and lightning will be the primary threats in addition to the locally heavy rainfall. Models in good agreement with this activity spreading east across the Plains and clearing into Kansas by Tuesday morning. Overnight, a cold front is forecast to drop south across the Plains turning flow northerly and ushering slightly cooler air. For Tuesday, expect another round of showers and thunderstorms by the afternoon and evening. Initial development will be over the higher terrain, with southwesterly flow aloft pushing the activity off the mountains and across the Plains through the evening hours. Locally heavy rainfall will once again be possible with an elevated flash flood threat across burn scars. Temperatures will remain warm with lower to mid 90s expected over the Plains for both Monday and Tuesday. Wednesday into Thursday...high pressure is forecast to build back across Colorado with drier air moving back over the state. This will bring drier conditions to the region for both days. Isolated to scattered showers and thunderstorms, primarily over the mountains are forecast. These showers and thunderstorms look to be diurnally driven and should dissipate through the evening hours. Temperatures will warm back into the lower to mid 90s across the region. Friday into Saturday...an upper disturbance passing to the north will send a cold front south into the Plains on Friday afternoon. This will turn flow more easterly with cooler air working into the region. The potential exists for more widespread showers and thunderstorms for both Friday and Saturday across the region. There will also be a return to an elevated flash flood risk over area burn scars due to moist upslope flow across the region. Mozley && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 244 PM MDT Sat Jun 29 2019 VFR tonight at all terminals with a chance for high based VCTS at KCOS and KALS from late this afternoon into this evening. A period of gusty and erratic outflow winds will be possible at all terminals until sunset, as weak convection drifts off the mountains. On Sunday, convection will again develop over the mountains around 18z, and with increased moisture, expect storms to spread across lower elevations and impact all terminals beginning 20z-21z. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PETERSEN LONG TERM...MOZLEY AVIATION...PETERSEN
Area Forecast Discussion
National Weather Service Tucson AZ
305 PM MST Sat Jun 29 2019 .SYNOPSIS...High pressure will bring hotter temperatures the next few days. Lingering moisture from the south will bring a few afternoon and evening thunderstorms around the area as well, accompanied by strong gusty outflow winds. && .DISCUSSION...Isolated to scattered showers and thunderstorms continued to develop late this afternoon. Most of this activity has been confined to areas near Tucson south to Nogales and east to around Willcox and Douglas. Very similar location and timing as depicted by the HRRR model early this morning. The latest HRRR solution showed a few lingering showers or thunderstorms through 09Z Sunday which still looked reasonable. Otherwise, Tucson managed to reach 109 degrees today which was a couple of degrees hotter than yesterday. Still looking at hotter than normal high temperatures the next few days as high pressure aloft remains in place. These hot daytime temperatures along with lingering moisture will keep the shower and thunderstorm chances in the forecast through early next week. Thereafter, models suggested a drop off in thunderstorm chances until late next week into next weekend when moisture returns. && .AVIATION...Valid through 01/00Z. SCT-BKN deck AOA 10k ft MSL and another layer of cirrus above through much of the period. Isol`d to sct -TSRA/-SHRA continuing this afternoon, at or around KTUS, KDUG and KOLS, particularly near terrain. SFC wind mainly WLY/NWLY at 6-10 kts with gusts up to 16 kt around KTUS and KOLS and to the west. To the east, sfc winds mainly SELY/SLY under 12 kts. -TSRA could produce brief gusty outflow winds of 30-40 kts. -TSRA/-SHRA expected to dissipate after sunset with winds becoming light and terrain driven. Much of these conditions are expected to return tomorrow afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Lingering moisture into next week will bring daily shower and thunderstorm chances to the region, particularly south and east of Tucson up to and beyond the state border. Convection will be high-based as is typical early in the monsoon with dry lightning an ongoing concern. The best chance for wetting rain will generally be across the higher terrain. Gusty and erratic outflow winds will be possible with any storms, with 20-ft wind speeds of 30-40 mph not uncommon. Outside of convection, 20-ft winds are expected to remain less than 15 mph through Monday with elevated southwest winds developing Tuesday and Wednesday. Daytime humidity minimums will dip to 10-15 percent through Sunday, with a very gradual increase in these values occuring next week. High temperatures through Monday are expected to be several degrees above normal before dropping to near normal Tuesday through the end of the period. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson