Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/21/17

Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
547 PM MDT Tue Jun 20 2017 .AVIATION... 00Z TAF CYCLE North to northwest flow aloft over New Mexico on east side of Four Corners high centered over east-central AZ and west-central NM. Isold tstms will continue until around 20/04Z across the southwest mountains and eastern plains. A few of the storms will contain brief MVFR cigs/vsbys obscg mt tops and wind gusts to around 45kt as well as hail. Potential for lcl MVFR cigs over the eastern plains aft 08Z. Storms will be mainly confined to the central mtn chain ewd Wednesday as dry air filters into southwest NM. 33 && .PREV DISCUSSION...335 PM MDT Tue Jun 20 2017... .SYNOPSIS... Very hot temperatures will persist through at least Thursday across the Land of Enchantment. A few storms will be possible each afternoon and evening, which may produce gusty winds and small hail. Some relief to the heat is expected on Friday, mainly across eastern New Mexico as a cold front slides through the plains and westward into the Rio Grande Valley. Moisture associated with the front will enhance thunderstorm chances Friday through at least the weekend. The thunderstorm activity should keep the triple digit heat at bay for at least through the first half of next week. && .DISCUSSION... Hot temperatures will remain the rule for the next few days as a 597dam high parks over the AZ/NM border. Dewpoints were up in the 50s this morning here at ABQ, but have since dropped to 17 with 5% RH. This has been the case across much of the RGV and points westward to the ContDvd, which allowed temperatures to soar. Temperatures will near records across much of central and western NM through at least Thursday, if not Friday. Will expand the Heat Advisory on Wednesday to include Espanola. Will also add in Thursday for the same areas, plus Socorro. As for storms, an axis of instability exists from the SW mtns across NE NM this afternoon, with the strongest instability across Union Co. per the LAPS analysis. Could see a few more strong or severe storms in this area through the evening, with hail and gusty downburst winds the main threats. Most models show a little complex of storms lasting well into the evening across the northeast, but should diminish by midnight. Wednesday should be similar to today, with the northeast being favored for storms in the aftn and eve again. Less storms are expected on Thursday, therefore, Thursday should be the hottest day of this stretch. On Friday, the upper high sinks southward as a trough crosses the northern Rockies. An associated back door cold front is expected to slide down the plains, and models are showing the front sliding through much faster than they were this time yesterday. Both the 12Z GFS and the 18Z NAM have the front completely through the plains by 18Z Fri, and pushing through the gaps of the central mountain in the afternoon. As a result, have lowered temps a few degrees across the east on Friday, particularly NE, but western areas will remain hot. The RGV will depend on just how fast and strong the front pushes into the area. The ECMWF remains much slower with the front, not bringing it down the plains until Saturday. Gusty winds can be expected along and behind the front. Low level moisture will be replenished behind the front which will likely enhanced thunderstorm chances Friday through the weekend with northwest flow aloft. Not out of the question to see a few strong or severe storms in this pattern, but shouldn`t see triple digit heat. 34 && .FIRE WEATHER... ...NEAR RECORD TO RECORD HEAT THROUGH THURSDAY AND POSSIBLY INTO FRIDAY... The upper high over New Mexico will continue to dominate through Thursday and into Friday but with some not so subtle changes starting to show up in the forecast models later this week. In the meantime, increasing instability with high Haines and some areas of Super Haines as well as near record to record heat and overall drying will become more widespread Wednesday and Thursday. Moisture trapped under the upper high will recycle for thunderstorms to develop Wednesday and Thursday over the higher terrain then drift into the valleys and plains, although the areal coverage and chances for wetting rain will be at a minimum Thursday. Much of any wetting rain may be relatively localized with many of the cells be more likely to produce gusty variable winds rather than much rain. For tonight, cell motion will be slow and somewhat erratic with storms drifting off the Sangre de Cristo mts and into the highlands and northeast plains. Farther south and west, motion will be the most variable. The NAM12 indicates a complex of storms dropping into ne NM later this afternoon/evening, creating a line of gusty north/northeast winds which pushes into the east central and along the east slopes of the central mt chain. This makes for difficult timing of any east wind into the RGV this evening/tonight. Both RAP and HRRR not nearly as aggressive with the thunderstorms over the east and therefore the surface gradient tonight. Northwest flow looks to strengthen some Wednesday and moreso Thursday/Friday as the upper high center retreats southward. The northern tier of zones, 101-102 and 103, may be most impacted by increasing winds/dryness as the theta-e axis shifts to the east and south. In fact, portions of the northwest plateau may see several hours of critical conditions combined with super Haines Thursday afternoon. Overnight humidity recoveries continue to be mostly good central and east tonight through Wednesday night with fair to locally poor recoveries west. Thursday night will be drier especially for the west and central where poor recoveries will be widespread after largely single digit humidities Thursday afternoon. Higher mixing heights Wednesday and Thursday lead to good to excellent vent rates over the majority of the forecast areas. Some of the forecast models are indicating the anticipated heat relieving front may be faster, and could reach ne NM as early as Friday morning then push into the RGV late Friday afternoon/early evening. Confidence isn`t the greatest due to the timing differences but the forecast is leaning towards a faster movement. While single digit humidities persist central and west Friday with some areas of Super Haines, the east will see improvement, and both min and max humidities trend upward over the weekend as high temperatures cool to near normal and below overall by Sunday. Chances for convection with wetting rain increase as well over the east, central and southwest. For next week, the drier westerly flow is nowhere in sight, models now indicate what looks suspiciously like a monsoon pattern for the middle of next week. Maybe picking up on climo. && .AVIATION... 18Z TAF CYCLE Upper high center over west central NM. Isold to sct tstms to develop over the higher terrain aft 18Z and drift into the valleys and plains. A few of the storms may contain brief MVFR cigs/vsbys obscg mt tops and wind gusts to around 45kt as well as small hail. Potential for lcl MVFR cigs over the eastern plains aft 08Z. && .ABQ WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 7 PM MDT this evening for the following zones... NMZ501>509-519. Heat Advisory from 2 PM to 7 PM MDT Wednesday for the following zones... NMZ501>509-517-519. Heat Advisory from 2 PM to 7 PM MDT Thursday for the following zones... NMZ501>509-517-519-520. && $$ 34
Area Forecast Discussion
National Weather Service Albany NY
1103 PM EDT Tue Jun 20 2017 .SYNOPSIS... An upper level disturbance will bring isolated to scattered showers mainly north and west of the Capital Region late tonight. Seasonable and comfortable weather is expected tomorrow into Thursday before warmer and more humid conditions return for Friday, along with a chance for showers and thunderstorms. && .NEAR TERM /THROUGH WEDNESDAY/... As of 11 PM EDT...A short-wave continues to move across the forecast area, as a few isolated showers continue across the Mohawk and Schoharie Valleys, as well as the Capital Region. The sky cover was tapered to partly cloudy or mostly clear prior to midnight, but another short-wave in the water vapor imagery moving across the central/eastern Great Lakes Region and Lake Huron is approaching western NY with the clouds increasing again. Scattered showers with an isolated rumble of thunder is moving across southeast Ontario and the eastern Great Lakes Region towards the Niagara frontier of the western NY. We trended the showers into the western Adirondacks and west-central Mohawk Valley after midnight. The instability looks weak with less than 250 J/kg, we placed a slight chc of thunder in for the western Dacks/western Mohawk Valley. We also tried to follow the last 3-km HRRR trends for the short- wave associated with the upper trough axis approaching early WED morning. Overnight lows will generally be in the mid 50s to low 60s. On Wednesday, the upper level trough axis will shift across the Northeast. There still may be a few isolated showers (perhaps a rumble of thunder too) across far northern areas, although coverage will likely be slightly less than today, with the best chance in. the late morning through mid afternoon hours. In addition, the threat for showers will start to decrease by later in the afternoon hours, as the better forcing starts to shift east of the region, as the upper level shortwave starts to depart. Otherwise, skies will be partly sunny and good mixing is expected once again thanks to the cooler temps aloft overhead. Some westerly wind gusts may once again exceed 20 mph during the afternoon hours with comfortable dewpoint levels in the 50s. High temps should reach the mid to upper 70s for valley areas (perhaps near 80 around Poughkeepsie) with upper 60s to low 70s across the hills and mountains. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A dry period of weather is expected Wednesday night through Thursday as a ridge of high pressure settles across our region. Lows Wednesday night are expected to be in the upper 40s to upper 50s with highs on Thursday in the upper 60s to lower 80s. However, another piece of upper energy begins to approach Thursday night with increasing warm advection and moisture. Scattered showers are once again possible Thursday night with the forcing and moisture advection associated with the increasing warm advection. Lows Thursday night in the upper 50s to mid 60s. Friday is expected to be unsettled with our area in a warm sector ahead of a cold front approaching from the Great Lakes with a zonal, southwest flow aloft. Guidance indicating a pre- frontal surface trough moving into our area during the afternoon, which would likely trigger showers and thunderstorms. Will have to watch for the potential for strong storms due to moderate instability and vertical wind shear. Highs on Friday are expected to be in the mid 70s to mid 80s. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The first part of the extended will be wet as we see a cold front pass through Friday night...setting off showers and possible thunderstorms. This will be followed by a mostly dry weekend as a second cold front over extreme southeast Ontario succumbs to gradually building high pressure originating over the Rockies. This broad area will be centered over the mid-south Tuesday. In the meantime, a developing wave along the cold front that passes through at the end of this work week will provide at least a chance of showers again for Sunday night and Monday, but this should be less substantial than Friday`s precipitation. Generally, day-to-day high temperatures will run the same or cooler, with upper 60s to lower 80s readings on Saturday becoming around 60 degrees to mid 70s highs by Tuesday. Lows will follow a similar pattern...with upper 50s to upper 60s readings Friday night becoming upper 40s to mid 50s by Monday night. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... VFR conditions are expected at the TAF sites for the entire TAF period ending at 00Z Thursday. A nearby upper level trough may allow for a few brief rain showers early this evening especially near the Mohawk Valley and Capital Region, but coverage/duration is fairly limited should wane with the loss of the diurnal heating. Further south, it looks to stay dry. All sites should have sct-bkn cigs at 5-7 kft early on, but will become few-sct shortly before or just after midnight. The winds will start to diminish this evening with the loss of daytime heating with the highest winds expected to stay under 10 kts. There will be just some few-sct high cirrus clouds overnight. During the day on Wednesday, an upper level trough will be located over the area. Daytime heating will allow for a few more clouds and the wind to pick up once again. Any isolated showers on Wednesday should remain mainly west or north of the TAF sites. West winds will increase to about 10 kts with some sct-bkn stratocu around 6 kft and some passing mid-level clouds as well. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: High Operational Impact. Likely SHRA...TSRA. Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday: Low Operational Impact. Slight Chance of SHRA. Saturday Night: No Operational Impact. NO SIG WX. Sunday: Low Operational Impact. Slight Chance of SHRA. && .FIRE WEATHER... Winds may gust to 25 mph Wednesday afternoon... Seasonable and comfortable weather is expected tomorrow into Thursday before warmer and more humid conditions return for Friday, along with a chance for showers and thunderstorms. Relative humidity values will recover to 75 to 100 percent tonight, drop to 40 to 60 percent Wednesday afternoon, recover to 75 to 100 percent Wednesday night, and drop to 35 to 60 percent Thursday afternoon. Winds will be southwest winds at 5 to 10 mph tonight, west at 10 to 15 mph with gusts to 25 mph Wednesday, and west at 5 to 10 mph Wednesday night and Thursday. && .HYDROLOGY... Scattered showers and isolated thunderstorms are in the forecast for Wednesday with more widespread showers and thunderstorms Friday after a dry day on Thursday. At this time most areas through Friday will have QPF values between 0.10 and 0.50 inch. Heavier rain may fall on Friday especially if some thunderstorms train over the same area. 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. && .EQUIPMENT... KGFL airport observation continues to experience intermittent communication issues. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis/11/Wasula NEAR TERM...Frugis/Wasula SHORT TERM...11/NAS LONG TERM...ELH AVIATION...Frugis/11/Wasula FIRE WEATHER...11/NAS HYDROLOGY...11/NAS EQUIPMENT...
Area Forecast Discussion
National Weather Service La Crosse WI
638 PM CDT Tue Jun 20 2017 .SHORT TERM...(Tonight through Wednesday Night) Issued at 143 PM CDT Tue Jun 20 2017 Current water vapor imagery coupled with RAP 500mb analysis shows the shortwave trough that gave the area morning convection now sliding southeast toward Lake Michigan. High pressure now building into our forecast area from the Dakotas/southern Canada. This high will slide southeast across the area overnight for partly cloudy skies. Given the rainfall that occurred today/moist ground, and mostly clear skies/light winds tonight, should see areas of fog, mainly over central WI where the ridge axis/lightest winds will reside longest. Farther west, along and west of the Mississippi River, there will be an increase in warm air advection mid-cloud which should inhibit radiational cooling/fog formation. Otherwise, looking for lows in the middle 40s in the Sand Country of central WI, to the lower/middle 50s elsewhere. For Wednesday, low pressure crossing the Dakotas will bring a push of warm air advection and moisture transport into the area by afternoon for a chance of elevated shower/thunderstorm activity. Highest chances look to be along/west of the Mississippi River where stronger push of moisture transport will exist. Otherwise, look for highs in the middle 70s to around 80. Showers and thunderstorms will become likely Wednesday night as moisture transport increases ahead/along of a cold front pushing into the area from MN. NAM/GFS showing 0-3km MUCAPE generally in the 1500-2000j/kg range with bulk shear values in the 25-40kt range. Bufkit soundings showing this convection would be mainly elevated in nature with LFCs generally above 800mb. At the same time, NAM is pushing precipitable water values into the 1.5 to 1.7 inch range. So, looking like a chance for a few strong to possibly severe storms with hail, heavy rainfall being the main threats. .LONG TERM...(Thursday through Tuesday) Issued at 143 PM CDT Tue Jun 20 2017 The aforementioned cold front pushing into the area Wednesday night looks to lay up across far southern WI/northern IL/IA by Thursday afternoon as it becomes parallel to the mid-level flow. Increasing moisture transport and lift over the front along with a fairly strong mid-level frontogenetic feature will produce the likelihood of showers/thunderstorms across our area. NAM/GFS showing MUCAPE increasing into the 2000-4000j/kg range by afternoon mainly along/south of I-90 with NAM displaying a whopping 50-60kt of Bulk Shear in the 0-3km layer. Taking a look at Bufkit soundings shows most of the thunderstorms over our area will have elevated LFCs north of the front for a large hail threat with the more surface- based storms/tornado threat across IL into IA. Of course, final outcome will be the exact position of the front which is still yet to be determined. In addition, with precipitable water values pumped up into the 1.7-2.0 inch range, these storms will be efficient heavy rain-makers. Will therefore have to keep a vigilant eye on the evolution of this scenario for severe potential. A longwave trough digs over the region for Friday through Tuesday. Shortwave troughs embedded within this cyclonic flow and steeper lapse rates will trigger daytime cumulus and the possibility of a few showers/isolated thunderstorms from time to time. Otherwise, look for cooler temperatures, especially on Saturday and Sunday with highs only expected to be in the 60s/lower 70s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 638 PM CDT Tue Jun 20 2017 The NAM develops some fog at KLSE late tonight. However both the GFS and RAP keep the boundary layer dry. With the diurnal mixing that took place on Tuesday afternoon, thinking that the RAP and GFS solutions seem more realistic, so went with them. A short wave trough will bring a broken mid to high deck of clouds to the area late tonight and Wednesday morning as it moves southeast through Iowa. A 6 to 8K deck of diurnal clouds will develop on Wednesday afternoon. There is a a chance of showers and storms on Wednesday afternoon, but confidence was not high to include them at this time. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION...Boyne
Area Forecast Discussion
National Weather Service Bismarck ND
954 PM CDT Tue Jun 20 2017 .UPDATE... Issued at 952 PM CDT Tue Jun 20 2017 Current POP trends too fast especially northwest into the central for this evening. Cut back for the evening until early morning. Otherwise current forecast ok. UPDATE Issued at 623 PM CDT Tue Jun 20 2017 Trimmed the early evening POPs back based on current CAM models and satellite and radar trends. Will see more showers and scattered thunderstorms develop as upstream shortwave and low to mid level warm advection develop around or after midnight. Otherwise current forecast looks good. && .SHORT TERM...(This evening through Wednesday) Issued at 256 PM CDT Tue Jun 20 2017 Highlights of the short term forecast period include isolated to scattered showers and thunderstorms tonight and early Wednesday, followed by a warm and breezy Wednesday afternoon. As of 19 UTC, isolated and high-based showers continue moving to the southeast and extend from about Watford City to New Salem and Fort Yates. Despite a dry lower atmosphere as sampled by the 12 UTC Bismarck and Glasgow RAOBs, some precipitation is reaching the ground per ASOS/AWOS observations and thus we have extended low- end precipitation chances through late afternoon in south central ND. Overall, the weak vorticity maximum embedded in northwesterly flow aloft on the leading edge of 500 mb height rises that seems to be driving this activity is forecast by recent RAP iterations to shear southeast and weaken by 00 UTC. Synoptically, a shortwave trough is expected to strengthen as it rapidly moves from western British Columbia this evening and into southern Manitoba by Thursday evening. A 35-45 kt southerly low- level jet is forecast to develop in advance of that wave tonight, and ascent based near 850 mb related to that wind maximum and the associated warm air advection will likely be sufficient to yield isolated to scattered showers and thunderstorms, mainly after 05 UTC and mainly from Minot to Jamestown per CAMs through the 18 UTC HRRR and 15 UTC ESRL HRRR. Forecast soundings show steepening mid- level lapse rates associated with an elevated mixed layer. We will lack rich moisture and MUCAPE for parcels lifted from about 850 mb will generally peak from 500 to 800 J/kg, so while a strong storm or two is possible, the probability of severe weather appears low at this time despite strengthening wind fields aloft. A mid-level thermal ridge will cross the region Wednesday ahead of a cold frontal passage that is expected during the afternoon. We leaned on the warmer edge of of model temperature forecast output for highs on Wednesday given expected deep mixing along and to the west of the frontal zone, and in respect to recent model biases. A low probability of convection will exist in the James River Valley during the afternoon, but we are downplaying any risk of strong or severe storms because we believe the prospects of deep convective development are highest east of the area per the 12 UTC NAM, GFS, and ECMWF simulations. The 09 UTC SREF calibrated severe storm guidance is also very low in our area Wednesday. Behind the front, northwest wind gusts to 30 mph are forecast with momentum transfer via cold advection in a deep boundary layer. Low humidities near 20 percent will yield some elevation in fire concerns, but fuel status may not yet support critical (red-flag type) designation. .LONG TERM...(Wednesday night through Tuesday) Issued at 256 PM CDT Tue Jun 20 2017 Much cooler, below-normal temperatures are expected late this week and into the weekend. The 12 UTC global model suite continued to advertise a trough at 500 mb developing over the region by Friday and lingering through the weekend. In general the last few GFS and ECMWF cycles have been trending drier during this time period, with a tendency for shortwaves embedded in the mean trough to be open waves instead of closed with deeper dynamics as some earlier iterations suggested. Thus, our forecast stayed the course with only a chance of showers in this period. Instability per model-derived CAPE fields is low and thus the probability for thunderstorms is low. Our confidence remains high in highs only staying in the 60s F in many areas on Friday and Saturday, before mid-level heights begin to rebound and yield a warming trend again by early next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 623 PM CDT Tue Jun 20 2017 A warm front extended from low pressure in Alberta southeast through eastern Montana. The warm front will be the focus for scattered showers and thunderstorms tonight northwest around 06Z moving into the central between 09-15Z. Otherwise VFR at all TAF sites through the 00Z period. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...CJS LONG TERM...CJS AVIATION...WAA
Area Forecast Discussion
National Weather Service Cleveland OH
858 PM EDT Tue Jun 20 2017 .SYNOPSIS... An upper level trough will gradually shift eastward across the Great Lakes through tonight. High pressure will build east across the area Wednesday and Wednesday night, with a warm front lifting northward over the area by Thursday. The front will push south on Friday reaching the Ohio valley by Friday night. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Update...Adjustments made to sky, pop, and hourly temps taking current conditions into expected trends based on the HRRR and satellite based timing. Original...Last piece of jet energy is currently diving through the west side of an upper level trough that remains over the central Great Lakes. Expect to see isolated/scattered showers/thunderstorms move across the area this evening into the early overnight. Lows tonight will be similar to last night. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/... Cold front looks as if it will be south of the area by late morning with all the shower/thunderstorm chances sagging southward with it. HIgh pressure will then increase its influence on the region Wednesday afternoon into Wednesday night. The frontal boundary will lift back to the north on Thursday with chances for thunderstorms increasing through the day. Better chances will be closer to Lake Erie. IT will be warmer and more humid on Thursday highs back into the 80s. A cold front will move into the central Great Lakes Thursday night and then sweep across the region at some point Friday evening. THunderstorms will become most numerous on Friday with some strong to severe storms possible. Still some uncertainty on how much impact cloud cover will have on the instability across the region. Friday will be another humid day with highs once again in the 80s. && .LONG TERM /SATURDAY THROUGH TUESDAY/... With only marginal moisture on Sat will stay with just small chc pops for shra or maybe and isolated tsra. The next s/w trough digging into the upper lakes will start to induce a surface low to develop somewhere near lower MI Sat night into Sun. Moisture is shown to pool over the area so will ramp up pops Sat night into Sun. The low and associated cold front should be shifting ENE of the area by Sun night so the threat for shra will taper off west to east. High pressure should build NE into the area Mon and still dominate on Tue. The high should try and provide dry wx Mon thru Tue but there will be an upper level trough over the area so some isolated convection could occur with daytime heating or off of lake erie late at night or in the morning. Near normal temps Sat into Sun will trend cooler by Mon then start to moderate a few degrees warmer for Tue. && .AVIATION /00Z Wednesday THROUGH Sunday/... A trough across SERN WI will move SE across the area overnight. A band of sct shra ahead of the trough will move across the forecast area overnight. Can not rule out an isolated rumble of thunder or two. OUTLOOK...Low chance of non-VFR Wed thru Sun in shra/tsra except good chance Fri into Fri night with passage of a cold front. && .MARINE... West winds of 15 to 20 knots producing marginal SCA conditions for the east part of the lake will diminish tonight as high pressure starts to spread north into the lake. The high will provide relatively light winds Wed that turn south by Thu then SW as the high shifts off to the east. A cold front should push SE across the lake later Fri into Fri night veering winds to the NW for late Fri night and Sat. Winds get more uncertain Sat night and Sun as a weak low may start to develop over lower MI and track near the lake Sun. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Beach Hazards Statement until 9 PM EDT this evening for OHZ012- 089. PA...Beach Hazards Statement until 9 PM EDT this evening for PAZ001. MARINE...Small Craft Advisory until 9 PM EDT this evening for LEZ147>149. && $$ SYNOPSIS...Mullen NEAR TERM...TK/Mullen SHORT TERM...Mullen LONG TERM...Adams AVIATION...DJB MARINE...Adams
Area Forecast Discussion
National Weather Service Cheyenne WY
618 PM MDT Tue Jun 20 2017 .UPDATE... Issued at 617 PM MDT Tue Jun 20 2017 Convection continues to expand in coverage over the mountains and high valleys, and even eastward toward I-25 where showers are currently developing off a number of llvl boundaries. Expanded PoPs accordingly. Do think a few hundredths of an inch of rainfall will reach the sfc with a few of the storms, but will continue to advertise gusty winds of 40 to 50 mph as well due to the dry sub-cloud layer. HRRR seems to be capturing current conditions pretty well, so increased PoPs slightly through tonight even further east into the Panhandle as the shortwave moves overhead. UPDATE Issued at 354 PM MDT Tue Jun 20 2017 Quick update to add some isolated thunderstorms into western Carbon County late this afternoon and early this evening based on latest satellite and radar trends. Any storms should be high-based and may not produce much in the way of precip but isolated instances of gusty winds may occur with any of these showers or storms due to the deep, dry sub-cloud layer. && .SHORT TERM...(This evening through Thursday) Issued at 150 PM MDT Tue Jun 20 2017 Weak shortwave energy will track to our north tonight. The strong upper ridge currently in place over the SW US will flatten somewhat on Thursday as a stronger shortwave moves quickly eastward along the Canadian border. At the surface, a weak trough/front will be located over western NE on Wednesday trailing southwestward into CO. This trough will weaken/wash out on Wednesday night as a second front drops south and across the area early Thursday. Wednesday will be another warm day and with the surface trough to our east initially, westerly to northwesterly boundary layer winds will limit moisture and thus chances for convection, especially with the continued presence of warm and dry air aloft. Early on Wednesday evening some isolated to widely scattered convection is possible over the mountains and along/east of the Laramie Range as winds turn more easterly and upslope. Heights aloft fall slightly on Thursday as the above-mentioned shortwave tracks to our north. In the post frontal environment on Thursday afternoon, models show fairly rich boundary layer moisture characterized by dewpoints in the upper 40s to low 50s returning east of the Laramie Range in northeasterly to easterly upslope flow. This moisture will be topped by steep lapse rates and moderately fast westerly flow aloft providing favorable instability/shear parameter space for the development of locally strong/severe convection. Best chances for this will be along the Cheyenne Ridge east of the Laramie Range where upslope flow should be able to be maximized and any cap overcome. Large hail looks to be the primary threat with this convection. .LONG TERM...(Thursday night through Tuesday) Issued at 150 PM MDT Tue Jun 20 2017 Thursday night: A few strong to severe thunderstorms still looks like a good bet mainly across the southern portions of Wyoming into the southern Panhandle. The NAM/GFS still are showing some capping taking place especially across the panhandle, but we are still concerned that some storms may fire along the Laramie range and may be able to push into the southern Panhandle Thursday evening despite the capping potential. Friday-Saturday: Cooler and drier conditions are in store for the area on Friday ahead of a much stronger cold front. This unseasonably strong front is progged to push through the area Friday night. A strong gradient is possible along this front, which may result in some abrupt changes Friday night. Temperatures may tumble into the 40s by midnight along with the potential for rain showers with even some snow showers possible in elevations above 9000ft. On Saturday,the ensembles are showing the surface high pressure (1028mb) nosing its way south along the Laramie Range on Saturday. In fact, the NAEFS ensembles are showing mean sea Level standard deviations about 2 to 3mb higher than normal for this time of year. This will most likely result in a very chilly morning on Saturday with lows starting out in the upper 30s in the Laramie Valley, and low to mid 40s east of the laramie Range. Meanwhile, afternoon highs may struggle to reach the 60s depending on how long the rain and cloud cover hangs on. Sunday-Tuesday: Temperatures should begin to moderate during this period as the upper level ridge slows builds into the area. In addition, drier conditions should be in store early next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 617 PM MDT Tue Jun 20 2017 Showers and thunderstorms will occur over portions of southeast Wyoming this evening, with a few showers potentially spreading east into the northern Nebraska Panhandle tonight. Impacts will be focused on gusty and erratic winds for any storms that move over the terminals. Otherwise, VFR conditions will prevail with widespread breezy northwest winds expected on Wednesday. && .FIRE WEATHER... Issued at 150 PM MDT Tue Jun 20 2017 Warm and occasionally breezy conditions will occur each afternoon through Thursday to the west of the Laramie Range. Fuels remain relatively green though which preclude much of a fire weather concern. Much cooler temperatures and some chances of showers/rain are on tap for Friday into Saturday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ UPDATE...RJM SHORT TERM...DEL LONG TERM...REC AVIATION...RJM FIRE WEATHER...DEL
Area Forecast Discussion
National Weather Service Dodge City KS
605 PM CDT Tue Jun 20 2017 ...UPDATE TO AVIATION... .SHORT TERM...(This evening through Wednesday) Issued at 151 PM CDT Tue Jun 20 2017 Afternoon CU developing along a surface boundary that extended from extreme southeast Colorado to north central Kansas earlier this afternoon. East of this boundary a southerly wind and surface dew points in the mid to upper 60s. Based on 18z verification it appears that the HRRR may have the right idea with the better chance for convection developing later today a along surface boundary in west central and north central Kansas. At this time the area most favorable to late day convection will be across north central Kansas given that it will be just east of the 700mb temperature gradient. 0-6km shear and mid level instability late today and early tonight suggests that any storm that does develop in these areas has the potential to become severe with the primary threat early in the event being 2 to 3 inch hail and strong damaging winds in excess of 60 mph. Once developed these storms are expected to move south across western Kansas early this evening. Still some question how long these storms will last early tonight but given the latest HRRR and 18z NAM the potential exists that these storms may hold together as they move all the way south to near the Oklahoma border based on the low level moisture axis and 25 to 35 knot 0-1km south winds. Will therefore keep a mention of ongoing convection through midnight for much of western Kansas. This evening the hail threat will decrease as these storms move south but strong winds and heavy rainfall will still be possible from some of these storms early tonight. On Wednesday 850mb temperatures warm into the upper 20s to lower 30s which suggests highs will climb into the upper 90s to around 100 degrees for all of western Kansas. By late day there will once again be a chance for some scattered strong to severe thunderstorms along a surface boundary which is forecast to be located once again near the Colorado border. Convection that does develop along this boundary late Thursday will move southeast again across western Kansas and is expected to weaken through the evening. The GFS does hint at a weak upper wave crossing southwest Kansas early Wednesday night which if this does occur may enhance convection and keep some night time storms going through at least midnight for locations west of highway 283. .LONG TERM...(Wednesday night through Tuesday) Issued at 151 PM CDT Tue Jun 20 2017 On Thursday the surface boundary/dry line will again be located from extreme southeast Colorado to northwest Kansas. 850mb temperatures at 00z Friday are forecast to be at or only a degree or two warmer compared to 00z Thursday. Highs once again around 100 degrees still look on track for western Kansas along with a chance for late day severe thunderstorms. Thunderstorm chances for western Kansas currently appears more favorable Thursday night as an upper level trough exits the central Rockies and crosses the West Central High Plains. Confidence is not high on how organized this convection will be as it crosses Western Kansas Thursday night but at this time this may be the better opportunity for widespread precipitation. Periods of heavy rainfall and gusty winds will be the main hazard should an organized complex of storms roll across western Kansas Thursday night. A stronger upper level trough will cross the plains on Friday and as it does a surface cold front will move across western Kansas. This will not only bring another chance for thunderstorms on Friday but also some cooler air is expected to return. Models over the weekend disagree on how much cooling will occur behind this front and how far this front will move before stalling out. At this time confidence is not on which solution is more correct so will stay close to the latest guidance for both precipitation chances and temperatures through the weekend into early next week. Despite the differences between the models over the weekend it does appear a break in the heat can be expected for western Kansas this weekend into early next week. Could easily have highs Sunday and Monday only in the 70s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 602 PM CDT Tue Jun 20 2017 Scattered thunderstorms will move southward across west central and southwest Kansas through late this evening, potentially affecting all TAF sites with MVFR cigs/vsbys. Brief IFR vsbys will be possible with the strongest storms. Otherwise, VFR conditions will prevail at all TAF sites through late Wednesday morning. Other than convective outflow winds from thunderstorms gusting in excess of 30 to 40kt, southerly winds 10 to 25kt will persist through early Wednesday as a lee side trough of low pressure remains anchored across eastern Colorado. && .PRELIMINARY POINT TEMPS/POPS... DDC 70 97 69 96 / 30 10 30 0 GCK 69 101 67 100 / 70 20 30 10 EHA 67 101 66 100 / 30 20 40 10 LBL 69 100 68 100 / 20 10 40 10 HYS 70 97 70 96 / 60 20 30 10 P28 70 95 69 95 / 20 0 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burgert LONG TERM...Burgert AVIATION...JJohnson
Area Forecast Discussion
National Weather Service GRAND JUNCTION CO
1004 PM MDT Tue Jun 20 2017 .UPDATE... Issued at 1001 PM MDT Tue Jun 20 2017 Added mention and increased coverage of showers and isolated storms for areas north of I-70 as a shortwave continues to track across northern portions of the CWA keeping shower and storm activity ongoing through the evening. HRRR is picking up on this better than most models and shows showers continuing to track eastward through the early morning hours before dissipating. Not getting much precip out of these showers with mainly gusty outflow winds the primary concern with a few lightning strikes here and there. && .SHORT TERM...(Tonight through Wednesday night) Issued at 200 PM MDT Tue Jun 20 2017 A large upper-level ridge analyzed at 596 DM over central Arizona remains firmly in control of the weather over the western CONUS this Tuesday afternoon. Along the northern fringes of this ridge, some mid-level moisture and a bit of faster flow aloft has resulted in convective development over the higher terrain of the Great Basin and middle Colorado River valley this afternoon. In northeastern Utah, around 500 j/kg of mixed-layer CAPE will fuel a few convective showers through the afternoon. Dry air near the surface as evidenced in model and observed soundings does not bode well for precipitation making it to the ground, however some locations in the Roan, Tavaputs, and eastern Uintas may see a hundredth or two out of any stronger cells that develop. Dry lightning will be a low, but not non-existent, threat this afternoon as one or two of the strongest cells may grow high enough above the freezing level to form graupel. Any convection will quickly wane after sunset this evening as daytime heating is lost. Temperatures this afternoon look on track as of 2pm, and will run near or just slightly below record values for the day. Despite 500mb heights lowering by 2-4 DM over the region uptick in winds aloft, some slight WAA from the southwest, and a bit better mixing will likely make Wednesday the warmest day of the year across the Four Corners. Slightly faster flow aloft will aid any convection that develops in the higher terrain north of I-70, and PoPs have been adjusted slightly upward in this package. .LONG TERM...(Thursday through Tuesday) Issued at 200 PM MDT Tue Jun 20 2017 The main forecast challenge in the long term will be with winds on Thursday. Forecast soundings from the NAM/GFS indicate the potential for mixing down winds of 20mph with some 30+ mph gusts across eastern Utah and especially northwest Colorado. The ECMWF is much less bullish regarding wind speeds at the surface, as it models the 300mb jet streak weaker and faster than its American counterparts. Due to the continued low confidence in this forecast, have opted to refrain from any Fire Weather headlines on Thursday for now. Future shifts will continue to monitor the forecast for any changes. After the passage of a weak frontal boundary on Friday morning, the heat wave will ease a bit as we head into the weekend. Some afternoon cloud cover will help curtail the warmth on Friday afternoon. Heights will lower notably by Saturday and Sunday. While temperatures are still expected to remain about 5 degrees above average, they will be 10 or so degrees cooler than the midweek-heat currently gripping the region. Late in the weekend, guidance is in fairly good agreement developing a new ridge of high pressure over the desert southwest. Eastern Utah and western Colorado will be on the eastern fringes of this ridge, and forecast models indicate a bit of lingering mid-level moisture lingering around the Continental Divide early next week. This would result in a better chance for showers and thunderstorms in the mountains than we have seen in recent days, before the ridge kicks this moisture east by midweek. Despite a relatively benign weather pattern upon first glance, there are certainly plenty of subtle forecast challenges to monitor through next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 748 PM MDT Tue Jun 20 2017 Scattered showers along and north of the I-70 corridor will persist this evening. There is a low chance that KASE and KEGE will see additional showers. Thunderstorms over the eastern Uinta Mountains may generate a strong outflow at KVEL before midnight. Otherwise, VFR conditions and CIGS above 18,000 feet MSL will continue through the night and through midday Wednesday. Showers and thunderstorms are expected over the mountains Wednesday afternoon resulting in conditions similar to today. && .FIRE WEATHER... Issued at 200 PM MDT Tue Jun 20 2017 Dry weather will continue over much of the forecast domain with only a small chance of convective activity in the Roan and Tavaputs as well as the eastern Uintas. Only trace amounts of precipitation are expected out of any development in these locations over the next two days. A low chance of some lightning does exist with any shower that develops. Winds will increase slightly during the afternoon on Thursday as a weak mid-level jet moves overhead. Under full mixing, some of these winds may translate to the surface resulting in near-critical Fire Weather conditions on Thursday. Confidence remains low on this borderline event and will not issue headlines as of this afternoon forecast package. && .HYDROLOGY... Issued at 200 PM MDT Tue Jun 20 2017 A flood advisory has been issued for the Roaring Fork River in Aspen as snowmelt and tunnel closures upstream have caused the river to reach bankfull. This advisory will run through Friday evening. A number of streams and creeks also continue to run strong, cold, and high and will continue to do so through the week. Where water is running high, river banks may become saturated and unstable. Lowlands along the rivers may also become inundated with water. Remember if you are going to raft, kayak or tube on the rivers be sure to always wear a life jacket. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...Heat Advisory until 10 PM MDT Thursday for COZ006. UT...Heat Advisory until 10 PM MDT Thursday for UTZ022-027-029. && $$ UPDATE...MDA SHORT TERM...MAC LONG TERM...MAC AVIATION...NL FIRE WEATHER...TGJT HYDROLOGY...TGJT
Area Forecast Discussion
National Weather Service Indianapolis IN
1023 PM EDT Tue Jun 20 2017 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 330 PM EDT Tue Jun 20 2017 Some chances for storms early tonight across the northern counties will give way to dry conditions for central Indiana for the most part until the remainder of a tropical system interacts with a frontal system to bring rain and thunderstorm chances across the area for Thursday night through Friday night. The front moving through will bring lesser chances for precip to the area until Sunday night once it has passed. Then dry, cooler weather moves in. && .NEAR TERM /Overnight/... Issued at 941 PM EDT Tue Jun 20 2017 A weak trough of low pressure was push across Central Indiana this evening. Weak instability along with the effects from daytime heating have allowed a few light rain showers and isolated thunderstorms to push across the area. HRRR shows a gradual dissipation of the showers and storms over the next few hours as heating is lost and best forcing is lost. Furthermore good subsidence remains in place near the Ohio River...which also should hamper further development and progression. Thus based upon radar trends have trendy pops high downstream of the echos...but have trended toward a dry forecast overnight as the forcing and instability is lost. Trended lows slightly cooler than the previous forecast...mainly across the northern areas that have seen some light rain fall. && .SHORT TERM /Wednesday through Friday/... Issued at 330 PM EDT Tue Jun 20 2017 On Wednesday surface high pressure and weak upper ridging will be over the area. These features currently look like they will be sufficient to quell any chances for showers along the washed out front during the day. For the most part dry weather will then continue until midday Thursday. By that point could see some low chances for thunderstorms start to move in from the south ahead of the tropical system. By late Thursday night a cold front will move toward the area from the northwest while the tropical remnants approach from the south. The highest chances for precipitation will be across the south. During the day Friday precipitation chances and amounts will increase as the bulk of the tropical moisture is drawn north and interacts with the aforementioned frontal boundary making rain likely and bringing chances for thunderstorms across most of the area. At this point bulk of model guidance keeps the axis of heaviest rainfall to the south of the forecast area, but this will be something to watch going forward. Highs Wednesday will likely be a couple degrees warmer than today with some warming at 850 mb and a mostly sunny day expected. Thursday should again be warm with a strong flow of warm moist air into the area. Friday though should see cloudy skies with the tropical remnants drawing further north, and this additional cloud cover should cap highs off in the low 80s. && .LONG TERM /Friday Night through Tuesday/... Issued at 253 PM EDT Tue Jun 20 2017 Showers and a few thunderstorms will linger into Friday night as a front across central Indiana moves on to the south. The front will be far enough south Saturday for Indiana to be dry. Models... especially the european indicate a weather disturbance may bring chance POPS around Sunday...then mostly dry weather will occur Sunday night through Tuesday as high pressure over the central plains moves towards the Ohio valley. Temperatures will be cooler than normal...especially Sunday and Monday. Highs will be in the upper 70s to lower 80s Saturday and again Tuesday and in the 70s Sunday and Monday. Lows will be in the lower to middle 60s Friday night...around 60 Saturday night and 50s Sunday and Monday night. Generally stayed close to model initialized temperatures. && .AVIATION /Discussion for the 210300Z KIND TAF Update/... Issued at 1023 PM EDT Tue Jun 20 2017 Scattered showers continue along an upper level disturbance from central Indiana back into east central Illinois. Threat for showers in the vicinity of the KIND terminal will linger for a few more hours. Will also make some adjustments to the wind forecast for the next several hours as winds expected to gradually veer around to the south or southeast in the wake of outflow boundary. Previous discussion follows. Upper level disturbance currently dropping southeast from the Great Lakes resulting in scattered convection over northern Illinois. Short term model guidance suggests this feature will pass over the terminals through about 210400Z. Instability axis runs from northern Indiana back into west central Illinois, with the air mass locally still fairly stable, so threat for lightning strikes should diminish with time this evening, but some scattered showers may linger longer into the evening. Best threat for lightning strikes at this time appears to be in the KLAF/KHUF vicinity, closest to instability axis. CB bases around 060. Briefly gusty and shifting winds possible near shower activity. Otherwise, scattered to broken clouds above 050 tonight. Surface winds 220-250 degrees at 8-12 kts early this evening expected to diminish to 6 kts or less late tonight. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CP NEAR TERM...Puma SHORT TERM...CP LONG TERM....JH AVIATION...JAS
National Weather Service Jackson KY
1047 PM EDT Tue Jun 20 2017 .UPDATE... Issued at 1047 PM EDT TUE JUN 20 2017 WSR-88D still picking up on a few isolated rain showers and/or sprinkles. These will remain light and most spots will remain dry tonight. Updated to allow a bit more time on the sprinkles and also updated clouds with latest obs and satellite trends. Also, the clouds are playing a role in keeping temperatures a bit warmer than the current temperature curve. Therefore, adjusted the curve some to better match trends. UPDATE Issued at 857 PM EDT TUE JUN 20 2017 Despite surface high pressure, a 500MB wave and 300mb divergence is just enough to POP off a rain shower or sprinkle this evening based on WSR-88D radar this hour. The HRRR seems to be handling this fairly well and will somewhat lean toward it with edits. For now will update to add in sprinkles at most for a couple of hour. These will be showers will be light and are expected to dissipate over the next couple of hours. UPDATE Issued at 625 PM EDT TUE JUN 20 2017 Surface high pressure continues to build into the region and matter of fact the highest pressure reading nearby is at CSV in the TN Valley region. Overall this and mixing will lead to a drier night and based on crossover temps not as much fog. However, while the CU will dissipate and we will be left with mostly high clouds streaming in from the SW. No major changes needed for this update but did load in the latest obs and trends. && .SHORT TERM...(This evening through Wednesday night) Issued at 359 PM EDT TUE JUN 20 2017 The latest surface map features broad high pressure across the mid-Mississippi Valley, with Tropical Storm Cindy located across the central Gulf of Mexico. Aloft, a strong ridge remains poised across the Desert Southwest, with troughing in the northeastern quadrant of the CONUS. Eastern Kentucky has been enjoying dry weather, with temperatures in the low to mid 80s and dew points down as low as the lower 50s in places at times. Dry weather will continue through the rest of the short term, as high pressure remains nosed in from the east southeast through the column. Tonight will feature a mostly clear night, with lows ranging from the mid 50s in some of the cooler valleys, and lower 60s on the ridges. Wednesday will feature a warmer day, with highs in the mid 80s, and dew points also a bit higher. The moisture will make a bigger increase through Wednesday night, as thicker high clouds stream in from the approach of Cindy. Lows will be in the mid to upper 60s. .LONG TERM...(Thursday through Tuesday) Issued at 359 PM EDT TUE JUN 20 2017 The extended portion of the forecast begins on Thursday with the upper level pattern favoring a more northern track with the jet leaving the central and southern CONUS under weak flow to begin the extended. Focus of the extended will be on the approach of the remnants of or rather a still organized Tropical Depression possible moving into Kentucky. Models have wavered a bit on the track and QPF amounts but overall have kept a consistent time period of rainfall. As the surface tropical low track north and northeast around the mid level ridge parked over the southeastern CONUS it will track east into KY and the TN Valley. At this point the system interacts with a cold front dropping from the western Great Lakes southeast into the Ohio Valley. Models have indicated, though slightly inconsistent on the placement of the heaviest band of precip, that this interaction with the front and the deep rich tropical moisture will produce the heaviest rainfall during the Sat 00Z to 12Z period. Model soundings during this time indicate a 2 inch plus PWAT over eastern Kentucky. However, the inconsistency of models and the lessened QPF of WPC 12Z solution has made the case to reduce QPF a bit so added a 50% blend to the super blend from the WPC run. Thus have gotten a more reasonable QPF amount and in agreement with the neighboring offices. So will continue to mention the heavy rainfall threat in the HWO for Friday through Saturday night with the best chance being Friday night into Saturday. By Sunday, expect a brief period of dry weather before the next disturbance tracks east across the mid MS Valley into eastern Kentucky by Sunday afternoon. The front will hang up along the middle Appalachians keeping the chance of precip lasting from Sunday afternoon into Monday afternoon. Confidence at this point is not very high given the uncertainty of the track of the remnants of Tropical system Cindy. Thus pop chances will be slight for Sunday night through Monday night. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 728 PM EDT TUE JUN 20 2017 We will remain VFR for the period as surface high pressure remains in control. Most sites are drier and crossover temps are not likely to be met. Therefore, fog will be limited to the deeper valley locations tonight. Kept the TAFs simple with CU disipating and only high to mid clouds expected overnight. The latest model soundings do show moisture at the 7k ft level again Wednesday afternoon and added this to the TAF. Winds will remain light, but west to southwest winds of 5 to 10 knots will mix down wednesday afternoon. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...GEOGERIAN LONG TERM...SHALLENBERGER AVIATION...DJ
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
939 PM EDT Tue Jun 20 2017 .DISCUSSION... MLB radar shows isold showers over the open waters and recent decictions of 2KM WRF and HRRR show at least isold activity continuing over the open waters and Gulf Stream overnight. The updated forecast keeps a slight chance (20%) for showers with a storm or two psbl over the Gulf Stream. Lows quite mild once again in the upper 70s along the coast and mid 70s inland. Prev disc... Wednesday...Little change in the overall weather pattern with a squeeze play between the Atlantic ridge to our east and Tropical Storm Cindy to our west. This will maintain deep southeast flow through the mid-levels. Expect a similar evolution of convection to today with isolated maritime showers moving onshore the Treasure Coast in the morning, transitioning to diurnally driven showers across the interior in the afternoon. Models indicate slightly better moisture developing during the second half of the day, so will carry 40-50% PoPs west of the St. John`s River. Elsewhere, 20-30% will suffice. Thursday and Friday...Surface high pressure ridge axis north of the area will keep a sustained southeasterly flow. For Thursday the best chance of showers and thunderstorms will be over the interior locations in the afternoon and evening with the inland moving sea breezes. The southeasterly flow continues on Friday but only have a slight chance of showers and thunderstorms as PWATs are forecast to be quite a bit lower than on Thursday. The "best" chance looks to be south of a line from Kissimmee to Melbourne where the GFS depicts wave of slightly higher PWATs moving into this area during the afternoon hours. Highs on Thursday and Friday will top out in the lows 90s inland and upper 80s to near 90 along coastal areas. Lows will continue above average with the persistent onshore flow. Mid 70s in most areas with some locations near the coast staying in the upper 70s. Saturday-Sunday...Mid level ridge builds east of the area and extends across the peninsula over the weekend through Sunday. This will bring some mid level drying to the area and lower mean moisture levels. Should see a more typical summer sea breeze regime with 20-30 percent rain chances near the coast and around 40 percent across the interior through Sunday. Monday-Tuesday...Rain chances will increase slightly Monday/Tuesday into the 30-50 percent range as a deep layer trough moves into the northern portion of the state and deep moisture ahead of the trough moves across East Central Florida. && .AVIATION... Dry conditions expected overnight with a low chance for onshore moving showers along the Treasure/Space Coasts. && .MARINE... Tonight...With the Atlantic Ridge to our east and Tropical Storm Cindy to our west, southeast flow will continue. A tighter pressure gradient will support 15 - 20 knots over the open waters, south of Cape Canaveral. Will carry Small Craft Exercise Caution headlines over the Brevard and Treasure Coast waters through tonight. Seas up to 4 feet nearshore and 5 feet offshore. Wed...SSE winds to around 15 knots the first half of the day will decrease to 10-15 knots in the afternoon. Seas 3-4 ft nearshore and up to 4-5 ft offshore. Thursday-Saturday...Winds/seas subside a bit as the Atlantic ridge axis drops back southward. SE to S winds 10 knots with seas 2-4 ft with isolated showers and storms expected. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ JP/AC
Area Forecast Discussion
National Weather Service Morristown TN
940 PM EDT Tue Jun 20 2017 .DISCUSSION... Latest IR imagery shows fairly extensive cirrus shield extending NE out of the Gulf Of Mexico and across the Tennessee Valley this evening as Tropical Storm Cindy sits in the Northern Gulf. With forecast for a northward drift expected overnight, do not expect to see any end to cirrus ceilings area wide. Updated forecast to reflect increased cloudiness through tonight. Additionally, decreased POP`s in SW NC for remainder of the night as radar echoes are beginning to weaken S of the area and any pcpn looks to remain S of the area through the overnight hours, in agreement with latest HiRes HRRR and RAP13. Tweaked temperatures/dew points slightly in order to bring in line with latest observations. Dew points have dropped into the upper 50s and lower 60s across much of the area, helping to make it feel a little cooler and drier on this Summer Solstice...which occurs at 12:24 AM tonight. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 68 85 70 82 / 10 20 30 70 Knoxville McGhee Tyson Airport, TN 66 85 68 82 / 10 10 10 50 Oak Ridge, TN 65 87 68 82 / 10 10 10 50 Tri Cities Airport, TN 61 84 64 81 / 10 10 10 40 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...None. VA...None. && $$ EJH
Area Forecast Discussion
National Weather Service Pueblo CO
324 PM MDT Tue Jun 20 2017 .SHORT TERM...(This evening through Wednesday) Issued at 324 PM MDT Tue Jun 20 2017 Currently... Skies mostly sunny for the most part across the cwa. ISolated thunderstorms were noted over the S Sangres S of KTAD. Towering cumulus were noted along the mtns, and along a lee trough that extended from E of KLAA down towards Kim, CO. It was quite warm across the region with temps in the 90s across nearly all of the plains. The warmest temp was in Pueblo with a reading of 97F. Instability was quite high east of the lee trough, with MLCAPE of 3500 J/KG with effective shear values of about 20 knots. Rest of the afternoon... One or two strong to marginally severe thunderstorms will be possible along and east of the lee trough this afternoon into early this evening. Storms should push off to the east-southeast and should move into KS by early evening. Other storms will be possible along the mtns/plains interface, especially south of Canon City. This evening into tonight... Simulations show that a weak short wave will move across the region late this evening into the early morning hours. The HRRR has been pretty consistent on indicating one or two storms will form across the Pikes Peak region around 10-11 pm and move east-southeast across the plains. For this reason have included some low POPs across this region for later this evening. Otherwise, expect mostly clear skies across the region with low temps 60s plains and 40s and 50s in the mtns. Tomorrow... We should see an uptick in convection across most of the cwa tomorrow afternoon as a weak boundary is expected to move down the plain. Temps tomorrow will actually be a degree or two higher tomorrow. Boundary should stall over far se CO and this will be a focusing area for convection. SPC has this area in marginal risk tomorrow and given the instability and inverted V soundings, strong gusty winds and some hail may be an concern. Mtns/plains interface may also see a slightly better chance of some thunder tomorrow along with a couple of storms in the interior mtn locations. Several 100F readings are likely along the lower ark rvr valley tomorrow. /Hodanish .LONG TERM...(Wednesday night through Tuesday) Issued at 324 PM MDT Tue Jun 20 2017 ...Cooling down for the Weekend... Wednesday night-Friday...Weak to moderate west to northwest flow aloft continues to be advertised across the State, with the center of large upper high across southern Arizona and southern New Mexico, and several embedded waves moving through the stronger flow aloft across the Northern Tier of States. Any high based convection across the area late Wednesday afternoon looks to diminish with the setting of the sun Wednesday evening. A stronger wave moving across the northern Rockies Wednesday night sends a front across the eastern Plains through the day Thursday, with low level moisture pooling along and behind the front. This front will be the focus for storms across eastern Colorado Thursday afternoon and evening, as it pushes southeast and west across all of the southeastern plains by early Friday morning. There could be a few stronger storms across northern portions of the area, generally along and north of the Palmer Dvd into northeastern Colorado, where the best shear will be located. Slightly cooler temperatures will be noted across the area Thursday, with a more noticeable cool down expected on Friday, with highs mainly in the 70s and 80s across the lower elevations and mainly 50s and 60s across the higher terrain. Morning stratus and easterly upslope flow look to keep the eastern plains too stable on Friday, though with the upslope flow, will likely see some storms develop across the eastern mountains and immediate adjacent plains Friday afternoon and evening. Saturday-Sunday...Models differ on Saturday, with the latest ECMWF still indicating another surge of cooler air digging across the area on Saturday, whereas the latest GFS is not as strong with the push of cooler air, keeping the main front across the northern high plains through the period. The GFS keeps moist south to southeast flow across the area Saturday and Sunday, owning to better chances of afternoon showers and storms, especially across the southeast mountains and plains, where as the EC solution would keep the plains generally too stable. For now, stayed close to model blended solutions which keeps slight chances across eastern Colorado through the weekend. Either way, temperatures look to stay generally below seasonal levels through the weekend. Monday-Tuesday...Upper level ridging rebuilds across the Desert SW and into the Great Basin, supporting a warming trend back to around seasonal levels into early next week. Some moisture embedded within the weak northwest flow aloft will also support increasing chances of afternoon and evening showers and storms across the area, most notable across the higher terrain. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 324 PM MDT Tue Jun 20 2017 VFR conditions through the next 24 hours. winds will be diurnally driven tonight. A weak weather disturbance will move across east central CO late this evening and there is a very slight chance of some -TSRA in the vicinity of KCOS between roughly around 05-06 UTC later this evening. A weak surge will come down the plains tomorrow morning and this may keep the winds northeasterly at KCOS and KPUB a good part of the day before becoming upslope late in the afternoon. There will also be an outside chance of a TSRA at KPUB and KCOS tomorrow afternoon. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HODANISH LONG TERM...MW AVIATION...HODANISH
Area Forecast Discussion
National Weather Service Blacksburg VA
920 PM EDT Tue Jun 20 2017 .SYNOPSIS... Variable cloudiness for tonight as a stalled front lifts northeast across southeastern Virginia. Weak high pressure remains in control on Wednesday. Weather turns increasingly more unsettled into Friday and Saturday with several periods of rain and embedded thunderstorms. && .NEAR TERM /THROUGH WEDNESDAY NIGHT/... As of 920 PM EDT Tuesday... Added a few showers in the west early tonight as highlighted on HRRR and HiResW-ARW-east, and continue light pops across southern portions of forecast area as frontal boundary lifts northward overnight into Wednesday morning. Modified cloud cover to capture sharp cloud gradient on satellite image. Made some minor adjustments in low temperatures to allow for cooler readings in the north with less cloud cover. Have a good night! As of 710 PM EDT Tuesday... Made some minor adjustments in temperatures for this evening utilizing surface obs with their trends and shaped towards glamp tonight. Slowed the drop of temperatures in the south with additional cloud cover. Trimmed back northern edge of light pops for the overnight. As of 325 PM EDT Tuesday... Overall a pleasant afternoon across the central Appalachians and into the Piedmont, along with a much-needed dry repreive from several prior days of wet weather conditions. Broad trough exists at 500 mb across the Great Lakes region, with upper-level moisture/high clouds stemming from circulation associated with what is now Tropical Storm Cindy in the central Gulf streaming northeastward. Weak surface ridge in place across the northern two-thirds of the forecast area, with a stalled frontal zone which trails across eastern VA into the central VA Piedmont and into Upstate SC. For Tonight: Generally quiet conditions tonight. Toward mid- evening, will watch a a mid-level shortwave trough embedded in the broad Great Lakes trough lift some of the deeper moisture associated with the stalled front back northeastward. The net effect this will have, though, is for an increase in clouds across the southeastern tier of counties in VA and in the Piedmont counties in NC. There may even be a isolated light shower from these but the prospect of that is not high. Honestly waffled between whether or not to call it a sprinkle or light shower, so definitely not significant. Patchy river fog will again be possible outside of the cloud shield and particularly in the New River and Greenbrier Valleys into the lower Tennessee Valley. Lows should be pretty similar to last night, in the mid 50s to near 60 east of the Blue Ridge and some 5-7 degrees warmer east of the Blue Ridge into the Piedmont. For Wednesday and Wednesday Night: Any light showers associated with the frontal wave dissipates by mid-morning, along with any river valley fog. Deeper west to northwest flow develops during the day, with mostly sunny to partly cloudy skies (mainly fair weather cloudiness with high clouds interspersed) from mid-morning through early evening. While most of the evening hours are dry, will be returning into a warm, moist advection pattern especially late in the night. Look for mostly clear skies to start, but with an increase in mid-level clouds late across the far southwest mountains of VA and the High Country of NC. Overall, looking for highs Wednesday in the upper 70s to mid/upper 80s (warmest northeast), with light west to southwest winds. Lows should be a few degrees warmer than tonight in the upper 50s to middle 60s, tending to occur a few hrs before sunrise with the increase in warm advection. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... As of 324 PM EDT Tuesday... Transition to tropical/muggy airmass commences this period as upper ridge of 588 to 590 DM builds across the southeast U.S. while what is now Tropical Storm Cindy heads into the LA/TX area. Westerlies aloft will stay north of us, from the northern Plains to the mid-Atlantic Thursday. Should see less of a threat Thursday of storm coverage, as models seem to confine activity more over the Southern Appalachians west and southwest to the Gulf Coast. With convergence in the low level winds and increase in moisture will still see a few showers/storms fire up in the afternoon. Best threat likes over the NC mountains/foothills into the Mountain Empire of Southwest VA. At the moment flooding threat looks marginal. Thursday night into Friday night, Cindy is expect to shift northward into Arkansas. A deeper northern stream shortwave will move across Ontario/Hudson bay digging a trough over the midwest, and causing heights to fall over our area. Models indicate a few pieces of energy moving east ahead of Cindy with potential for heavier rains shifting from KY/TN east/northeast to the Central Appalachians. Precipitable water values will be increasing to 1.5 to 2.0 inches and right now, rainfall Friday will be heavy at times, but still some question on where greatest corridor of rain will fall, with 12z GFS/ECM very close in having northern KY into Ohio, northern WV as the area to get the higher amounts. Given some uncertainty should still be a limited threat of localized flooding from downpours. As far as svr threat, thinking is with more clouds/tropical like soundings, the storms should stay sub-severe. Lows this period will be warm, about 5-8 degrees above normal ranging from the lower to mid 60s mountains, to around 70 to lower 70s east of the Blue Ridge. Thursday appears a little less cloudy in the east, so will see temperatures reach the mid 80s, possibly near 90 east of Danville, while the mountains get into the mid 70s to around 80. Friday should be a few degrees cooler with more clouds/rain around, but still noticeably muggy in the 70s mountains, to lower to mid 80s east. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 148 PM EDT Tuesday... Still looking muggy and showery this weekend, especially Saturday as remnants of now Tropical Storm Cindy get pooled in along a cold front moving in from the northwest. Model solutions favor Cindy weakening/eroding but some have it staying situated back over the mid MS Valley behind the front into Saturday then getting kicked east ahead of digging northern stream trough. So in terms of precip chances, Saturday looks like a good soaker, Sunday is iffy as but still chance is there with frontal boundary in the vicinity. Northern stream front moves across Monday morning so, overall Monday/Tuesday look drier and a little cooler. Temperatures this weekend will be seasonal but muggy, with highs in the mid to upper 70s west to lower to mid 80s east. Still early on flooding concerns with 12z GFS a little lower on QPF into Sunday keeping higher amounts west of the Appalachians. Will ease off some on the HWO wording, but localized flooding will remain the main concern. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... As of 719 PM EDT Tuesday... VFR conditions will continue at the taf sites this evening into tonight. In general, some SCT CU expected with some high level clouds especially in southern portions. Tonight into Wednesday morning, the frontal boundary`s northeast advance may push MVFR clouds, SCT020 to BKN020 into KDAN. There may even be an isolated unrestricted shower or sprinkle. With such a high clouds base, have low confidence in precipitation. However, the NAM and HRRR still support an isolated showers across the extreme southeast portion of the forecast area. Radiation fog is possible with higher confidence of MVFR/temporary IFR visibilities at KLWB and KBCB. Potential is there at KLYH as well but a little less confident there as it will depend on extent of cloudiness. Held on to some light fog after 09z for Lynchburg. Winds should trend light and variable tonight. Should trend VFR again Wednesday, though like today, greater low to mid-level cloud cover further southeast. Winds again become west to southwest 4-8 kts. Extended Aviation Discussion... Generally VFR Wednesday late afternoon through Thursday afternoon. Low-confidence prospect for radiation fog Wednesday evening into Wednesday night. More active aviation forecast period Thursday evening into the weekend. Lowering, sub-VFR conditions anticipated Thursday evening into Friday with first surge of showers advancing SW to NE. Potential for low-level wind shear western terminals. Continuation of sub-VFR conditions Friday evening into Saturday with moderate to at-times heavy rain. Confidence is low on timing of rain. The unsettled weather continues Sunday into Monday with sub-VFR condition possible with convection. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AL NEAR TERM...AL/KK SHORT TERM...WP LONG TERM...RAB/WP AVIATION...AL/KK