Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/08/18

Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
506 PM MDT Sat Jul 7 2018 .AVIATION... 00Z TAF CYCLE Upper high will continue to be centered over wrn CO with shower and storm motion generally from northeast to southwest. Outflow boundaries with gusts to around 45kt producing lcl MVFR vsbys in bldu may also spark randomly moving storms. Lcl MVFR cigs/vsbys and small hail in the stronger storms should be relatively brief along with any related terrain obscurations. Short term models suggest there may be lcl MVFR cigs around 06Z-08/15Z over the ern plains, and some lingering precipitation over sern NM. Otherwise precipitation should taper off aft 06Z. && .PREV DISCUSSION...302 PM MDT Sat Jul 7 2018... .SYNOPSIS... Daily rounds of shower and thunderstorm activity is expected over the next several days, however storm coverage will trend downward on Monday and Tuesday. Given high atmospheric moisture content, some storms will be efficient rainfall producers and may cause flash flooding on burn scars. The rain and cloud cover will keep temperatures at or below July normals. && .DISCUSSION... As expected, showers and thunderstorms are more numerous this afternoon as compared to yesterday afternoon. Steering flow is taking these storms slowly to the southwest. The HRRR and RAP suggests that a few storms may try to roll into the ABQ Metro area late this afternoon or early this evening. Otherwise, should focus across western NM after 00Z. Storms so far today have been capable of small hail and torrential rains. This will persist into the evening, with flooding over burn scars will be the biggest threat. Storm coverage, motion and placement should be similar on Sunday, perhaps slightly less along the east slopes of the central mountain chain. PWATs will remain around an inch, so any storms that do develop will continue to be efficient rainfall producers. A downtick in storm coverage is expected Monday and Tuesday as some drier and more stable mid level air shifts into the area from the northeast. There will still be isolated to widely scattered storms over the high terrain, but the southwest mountains will be the most favored. Storm motion will be more toward due west. It should be noted that even though storm coverage will be less overall, it only takes one storm to cause a problem over a vulnerable area. Storm coverage should gradually increase Wednesday through Friday, particularly across central and western NM as the dominant upper high shifts to the east. Daily rounds of thunderstorms are expected with weak steering flow. Heavy rain and flooding will remain possible. 34 && .FIRE WEATHER... Scattered showers and thunderstorms over NM today will continue producing locally heavy rainfall and strong outflow winds. Storm motion will be slow toward the southwest. The focus for storms will shift into the northern and western higher terrain Sunday as drier air aloft pushes into the eastern plains. Upper level high pressure will strengthen over western Nebraska Monday and Tuesday and force a more stable airmass with drier air aloft across NM. This will focus moisture and instability over AZ early next week. There will still be the threat for locally heavy rains from any storm since steering flow will be very weak. Extended guidance is now in slightly better agreement that the main monsoon moisture plume will focus over AZ through as late as next Thursday before shifting back east over NM by late week. This would trend humidity lower with temperatures trending closer to normal. Guyer && .AVIATION... 18Z TAF CYCLE Clouds building over the high terrain will develop into sct SHRA/TSRA thru 20Z. Storm motions will be to the southwest around 10 kt. The exception will be southeastern NM where TSRA are drifting to the west. The coverage of TSRA will increase thru 22Z with a peak thru 02Z. Direct hits will be capable of strong outflow winds, frequent lightning, and MVFR cigs/vsbys in heavy rainfall. The bulk of storm activity will taper off thru 04Z however guidance is trending toward SHRA/TSRA for much of the night around KROW. && .ABQ WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch until midnight MDT tonight for the following zones... NMZ512>515-528. && $$
Area Forecast Discussion
National Weather Service Bismarck ND
955 PM CDT Sat Jul 7 2018 .UPDATE... Issued at 955 PM CDT Sat Jul 7 2018 Once again, little change was made to the gridded forecast except to blend observational trends and recent rapid-refresh guidance into hourly elements through early Sunday morning. The latest thinking on the severe-storm risk is contained in the mesoscale discussion section from 934 PM CDT below. && .MESOSCALE DISCUSSION... Issued at 934 PM CDT Sat Jul 7 2018 The risk of severe weather is increasing over southwest and south central ND, and is expected to peak in the 05 to 10 UTC window, though the exact evolution of storms overnight remains somewhat uncertain. The 00 UTC Bismarck sounding sampled rich low-level moisture with a mean lowest-100 mb mixing ratio around 15 g/kg surmounted by steep midlevel lapse rates on the order of 8 C/km in the 700-500 mb layer, yielding strong potential instability. However, a warm nose between 850 and 700 mb was sufficient to yield greater-than- forecast inhibition for mean lowest-100 mb parcels as a result of a somewhat shallower moist layer depth than models had expected. This -- along with a continued weakening of the frontal zone in central ND through the evening -- was likely sufficient to keep earlier convective initiation at bay. As of mid evening, surface observations show weakening wind fields and even a return to a more southerly component across most of western and central ND such that low-level moisture advection has resumed in most areas in a magnitude greater than earlier modeled, as exemplified by a return to 70 F dewpoints at Garrison. This implies that the sharp northward gradient in instability and thus severe risk portrayed by RAP-based analyses such as the SPC mesoscale analysis may be less intense than suggested, which in turn may make it even more difficult to narrow down the area of greatest severe risk through the next several hours. However, continued advance of midlevel cloud decks through central ND suggest that synoptic-scale ascent may continue to weaken inhibition the next several hours atop the rather broad area of strong to extreme bouyancy in place across the area, and the area of intensifying convection in southeastern MT is of particular interest, particularly since it is occurring in a region of well-defined surface pressure falls, which is further suggestive of a stronger impulse aloft that could assist in sustaining convection east-northeast across southwest and into south central ND overnight. Given MUCAPE of 3000-5000 J/kg and effective-layer bulk wind differences on the order of 40 kt we expect both severe hail and wind risks with this event. Based on west-southwest deep-layer shear, mean wind, and anvil-level wind vectors that are largely normal to the residual low- to midlevel frontal zone that is broadly oriented in a northeast-southwest fashion, which may favor at least some upscale growing clusters and an attendant severe risk through the night, including some potential for development of a forward-propagating complex. && UPDATE Issued at 810 PM CDT Sat Jul 7 2018 Quick update to allow the Heat Advisory to expire on schedule. A few locations are still reaching headline criteria as of the top of the hour, but heat indices will ever-so-slowly continue to ease downward the next few hours, so we let the advisory expire. UPDATE Issued at 650 PM CDT Sat Jul 7 2018 Little in the way of change was made with this update. Recent HRRR and ESRL-HRRR cycles key on post-frontal thunderstorms developing in the 04-06 UTC time frame roughly along and north of Interstate 94 from Dickinson toward Bismarck and Jamestown, but we are still monitoring for the low probability of earlier development as some earlier-day CAMs supported in south central ND. See the mesoscale discussion section below for more technical details. Otherwise, we chose to continue the Heat Advisory as-is for now, despite the fact that heat indices in its western extent are below the 100 F technical criteria for the headline, but we fully anticipate that we will be able to let it expire at 01 UTC. && .MESOSCALE DISCUSSION... Issued at 555 PM CDT Sat Jul 7 2018 The near-term probability of convective initiation and an ensuing severe-storm risk appears low -- but not negligible -- through 00 UTC. GOES-16 one-minute visible satellite imagery per mesoscale domain sector number two has been showing persistent, but shallow cumulus fields along a weak pre-frontal trough and the more well-defined shift to west-northwest winds that marks a weak cool front across east central ND the last few hours. The cumulus has at times shown tendencies for increasing coverage, perhaps suggestive of regions of enhanced meso-beta or meso-alpha-scale low-level ascent, but we have yet to see any defined vertical growth to the cumulus fields. The 22 UTC surface analysis revealed a relatively large corridor of middle 70s F dewpoints in east central and eastern ND -- which is contributing to MLCAPE on the order of 5000 J/kg and minimized MLCIN centered on the Carrington region per RAP-based objective analyses -- but it also showed veered surface winds in the frontal zone, implying a lack of low-level convergence and ascent. Model- derived soundings suggest that while MLCIN may be minimal over parts of east central ND, a warm nose may still be centered in the 760 mb layer, and veered southwest flow in the LFC to LCL layer could be yielding detrimental parcel detrainment along the frontal boundary, as well. Finally, the low-level thermal ridge axis with surface temperatures of 95+ F -- which extends as far north as Mobridge, SD -- does not intersect with the front or pre- frontal wind shift across the local area (but does in northeast WY where storms have developed already this afternoon). Taken together, this suggests that the odds of convective initiation through at least 00 UTC is low, but we will continue to monitor in case isolated development occurs in the strong-extreme CAPE and moderately-sheared environment that would likely yield intense updrafts given initiation. More importantly, the midlevel cloud decks streaming across western and into north central ND may reflect greater ascent and related cooling aloft that could eventually aide storm development in the immediate post-frontal environment later this evening. && .SHORT TERM...(This evening through Sunday) Issued at 109 PM CDT Sat Jul 7 2018 Scattered strong to severe thunderstorms are expected this evening and through tonight. Uncertainty regarding timing and location of convective initiation remains. Current surface weather observations show a pressure trough along a weak, slow-moving cold front located across western North Dakota early this afternoon. This front will be the focus for convective initiation later this evening. The latest CAM model guidance shows rather drastic differences in the timing, location and coverage of storm development. The 12z iteration of the HiResW-NMM-East has convection initiation around 00z, the NAMNest around 01z, and the HRRR around 05z. With the 12z KBIS observed sounding showing a strong cap with MUCIN over -350 J/kg and 850 mb temperatures around 27 degrees Celsius, it is difficult to say when the most likely time for convective initiation will be. There is little to no upper-level forcing for this event, so initiation will depend almost solely on the mesoscale forcing along the cold front. When storms do finally form, some will likely become strong to severe given the extreme instability with MUCAPE values in excess of 4000 J/kg and bulk shear generally between 30 and 40 kts. Storms will likely linger into Sunday morning across southeast North Dakota as they slowly push eastward, with conditions drying out across all of western and central North Dakota by the afternoon hours. .LONG TERM...(Sunday night through Saturday) Issued at 109 PM CDT Sat Jul 7 2018 Heat builds back up early this work week, with an overall drier pattern expected throughout the long term forecast. The 12z iterations of the GFS/ECMWF show nearly zonal flow across western and central North Dakota Sunday night, with a large upper level ridge building in on Monday and peaking on Tuesday. Slight chances for thunderstorms exist Monday night as a weak impulse moves along the upper level ridge. Ridging will allow temperatures to rise well into the 80s on Monday, and into the 90s on Tuesday across western North Dakota and parts of central North Dakota. Despite the hot temperatures, surface dew points look to be too low to create heat index values over 100 degrees on Tuesday. The latest suite of model guidance shows mainly dry weather across western and central North Dakota Tuesday through Friday morning, with above average temperatures. A weak impulse moves through northern North Dakota Friday afternoon and evening, bringing with it chances for showers and thunderstorms. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 955 PM CDT Sat Jul 7 2018 Scattered strong to severe thunderstorms are expected across southwest and south central ND through the James River valley tonight. KDIK, KBIS, and KJMS could be impacted, but confidence in storms impacting any given location remains low given the weak nature of the front in place across the area. Thus, radar trends will likely dictate amendments to TAFs as needed. Localized MVFR to IFR conditions are possible in any storms that occur, but otherwise VFR weather is generally expected for the 00 UTC TAF cycle. The probability of storms will be relegated to the James River valley region by Sunday. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CJS MESOSCALE...CJS SHORT TERM...TK LONG TERM...TK AVIATION...CJS
Area Forecast Discussion
National Weather Service Flagstaff AZ
327 PM MST Sat Jul 7 2018 .SYNOPSIS...Scattered showers and thunderstorms activity is expected overnight across northeast Arizona. Otherwise, the monsoon weather pattern will persist over the region through next week, with daily rounds of afternoon and evening thunderstorms. The highest rain chances are currently expected on Monday and Tuesday. && .DISCUSSION... Scattered to numerous thunderstorms have developed today across western Arizona, with several reports of .50 to nearly an inch of rainfall and a few reports of pea to marble sized hail. For tonight through Monday afternoon...We have followed the HRRR and UA WRF models closely for tonight. These models continue to show high pressure aloft centered over Colorado with light east and northeast flow into Arizona. QPF panels show rainfall tonight across the northeast quarter of the state as a disturbance moves from the 4 corners southwestward overnight. Scattered storms are expected for Sunday and Monday. On Sunday, covection likely to start first over the highest terrain of Coconino County, while the eastern Mogollon rim and White mountains should see a delayed start as this area may be recovering from tonights disturbance. From Monday night through Friday. Moisture increases with potential for some dynamics as an inverted trough drifts through southern Arizona Monday and Tuesday. This should be a much more active period as improved moisture also arrives due to a shift in the transport winds. && .AVIATION...For the 00z package...Expect isolated to scattered -SHRA/-TSRA over northern Arizona through 12Z Sun due to a disturbance moving from the Four Corners southwestward. An early morning break in preciptation is expected through 17z, then scattered storms redevelop over the higher terrain. MVFR conditions with gusty outflow winds near any storms. Otherwise VFR conditions expected away from thunderstorms, with variable winds to 10 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect increased shower and thunderstorm activity across northern Arizona through Monday. A disturbance moving from the four Corners southwestward tonight should produce scattered showers and storms tonight. Tuesday through Thursday...The monsoon pattern continues across northern Arizona for this period. Expect scattered to numerous afternoon and evening showers and thunderstorms, with better chances for widespread wetting rains each day. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...DL AVIATION...DL FIRE WEATHER...DL For Northern Arizona weather information visit
Area Forecast Discussion
National Weather Service Hastings NE
800 PM CDT Sat Jul 7 2018 .UPDATE... Issued at 800 PM CDT Sat Jul 7 2018 A few notes for this evening`s forecast/product update: 1) Although a rogue shower managed to pop up slightly outside our far southern CWA in Ellis County KS a little earlier, unlike yesterday evening, no daytime-heating-driven activity managed to affect southern portions of our domain. Now that the sun is going down and visible satellite clearly shows diurnal cumulus fading away, any small chance of thunderstorms that once existed in our southern zones has since ended, and have "cleaned up" our short- term Hazardous Weather Outlook (HWOGID) as a result. 2) Although still several days away, decided to introduce a mention of heat index values of 100 degrees or slightly higher to our HWO for Wednesday-Friday afternoons, as this appears to be our next chance of having at least "near-Advisory" heat levels, mainly within our far southern/eastern zones. This also matches us better with neighboring offices such as OAX/TOP/ICT/LBF, who already had a heat index mention going in their respective HWO products. 3) The forecast for the rest of tonight appears to pretty much be on "auto-pilot", with clear skies, virtually zero chance of rain/storms, south-southeast breezes around 10 MPH-or-less, and overnight lows eventually settling into mainly the upper-60s. && .SHORT TERM...(This evening through Sunday) Issued at 302 PM CDT Sat Jul 7 2018 Just enough low-level moisture and lapse rates for me to throw in some isolated pops mainly over north-central Kansas. We don`t have the divergence aloft and well-defined instability axis as we did yesterday, so I am not looking for a lot of activity here. Models are not generally handling short-term convection well, but the latest HRRR indicates the possibility of small pop-ups into mainly our north central Kansas counties, and perhaps just into Nebraska, mainly over the area of slightly more favorable low-level lapse rates. Persistent and intense upper ridge continues to expand east and will provide a warm and dry forecast with lows tonight in mid to upper 60s and highs Sunday near 90 to the lower 90s. These temperatures are a bit above normal, which is what one would normally expect with an upper ridge as in this case. Flow will remain rather weak aloft as the jet stream lies primarily in southern Canada near the US border. .LONG TERM...(Sunday night through Saturday) Issued at 302 PM CDT Sat Jul 7 2018 Flow remains weak for the long term as the upper ridge strengthens its influence at the beginning of the long term period. Ensembles indicate a potential weakness from a wave skirting the northern periphery of the upper ridge, possibly flattening or breaking down the previous amplification. This may possible allow the ridge to turn a bit farther south, which could possible send it far enough south to give us a small shot at rain/thunder by the end of the work week. Given the strength of the upper high, this may be a bit of a stretch, but appears to be the next possible chance of precip. With the anomalously strong high, comes somewhat above normal temperatures with highs in the 90s and lows in the 65-75 range. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday) Issued at 616 PM CDT Sat Jul 7 2018 Confidence is very high in continued VFR ceiling/visibility and rain/storm-free weather with little if any cloud cover, and any possible light haze around sunrise not expected to drop visibility below 6SM. If anything, probably got a bit too detailed with wind trends in the TAFs, but the bottom line is that a generally southerly direction will prevail throughout, with sustained speeds at-or-below 12KT most of the time, and the overall-strongest speeds with gust potential around 20KT focusing between 18-22Z Sunday afternoon. Any low level wind shear (LLWS) overnight appears to be a bit marginal to formally include at this time (shear magnitude only topping out around 25KT). && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ UPDATE...Pfannkuch SHORT TERM...Heinlein LONG TERM...Heinlein AVIATION...Pfannkuch
Area Forecast Discussion
National Weather Service Medford OR
804 PM PDT Sat Jul 7 2018 .UPDATE...Smoke continues to pour from the Klamathon Fire, filling the Shasta Valley, and overspreading much of the region along and east of the Cascades. Once daytime winds clam, overnight inversions will allow the smoke to settle into area valleys once again. Prevailing winds above the surface remain from the southwest, while surface winds remain northerly. This means the same areas that saw smoke this morning and today are likely to see the same, if not more, tomorrow. No updates were needed this evening, other than to refine expected smoke coverage. For more information on the rest of the forecast, see the previous discussion below. && .AVIATION...For the 08/00Z TAFs...Smoke from Klamathon Fire will lower visibility across the Shasta Valley of northern California to MVFR with IFR vis likely in valleys where smoke settles overnight. With southwest steering winds, smoke has drifted into the southern Oregon Cascades and the Klamath Basin and vis at LMT has gone down to MVFR. Expect terrain and mountain obscuration in these areas. HRRR smoke model shows condition remaining steady overnight as northwest winds keep denser smoke and lower visibility in northern Siskiyou County. However winds on Sunday are expected to shift to southerly and the smoke model bring denser smoke and lower visibility to LMT from late morning (18Z) through the remainder of Sunday. We have gone with MVFR vis for LMT but occasional IFR vis from smoke drifting in and out is possible Sunday. For the coast, patchy MVFR cigs are likely to form again tonight, mainly north of Cape Blanco, and in the Coquille and Umpqua Basins. VFR conditions are expected elsewhere overnight and into Sunday. -FB && .MARINE...Updated 800 PM PDT Saturday 7 July 2018...Relatively calm conditions will continue through the weekend. Seas will remain at or below 5 feet through Monday and northerly winds will remain below small craft advisory levels. Although the wind forecast for this afternoon and evening has been decreased, areas south of Cape Blanco and within 30 nm from shore may see a few wind gusts approach small craft advisory levels. Near shore, some fog and low clouds may develop tonight from Point Saint George north to Brookings or Gold Beach. The thermal trough will redevelop Tuesday. Winds will steadily increase next week, with small craft advisory winds and seas likely developing Monday evening into Tuesday for areas south of Cape Blanco. Then winds and seas increase further Tuesday evening and Wednesday, possibly reaching gales. Gusty winds with steep to very steep seas are possible north of Cape Blanco by mid week. -BS/BPN && .FIRE WEATHER...Updated 300 PM PDT Saturday, 07 July 2018... Breezy southwest winds are ongoing east of the Cascades and the eastern portions of northern California this evening. These conditions will continue into tomorrow, but the airmass is expected to dry out even more compared to today , Saturday. This drying will result in some single digit RH values in northern California and south central Oregon on Sunday. Given the drier airmass, we believed another red flag warning was needed. RH`s will trend higher on Monday with winds trending slightly lower over the region. It appears the slightly higher RH`s will keep us out of red flag warning criteria, but the winds Monday should be similar to the winds on Sunday. With this upcoming warm up, models are expecting a thermal trough and offshore winds to build along the Curry County coastline. This should bring lower RH`s to that region in addition to some breezy winds for the middle of the week. Temperatures are expected to push into the 90`s and 100`s next week Wednesday into the weekend. We`ll also have the chance for thunderstorms Thursday into the weekend as some monsoon moisture comes out of the southwest. -Smith && .PREV DISCUSSION... /Issued 520 PM PDT Sat Jul 7 2018/ DISCUSSION...Dry and gusty weather continues into Sunday east of the Cascades. Although an upper level trough begins to move into the region Monday, heights remain relatively constant into Tuesday when the axis of the trough moves through the region. A weak front offshore washes out with the tail end of the frontal precip brushing inland well north of the region. the result of this trough passage will mostly be a slight cool down Monday that remains into Tuesday, and north winds prevailing down into California for both days. An upper ridge then builds behind the exiting trough offshore with heights rising, a thermal trough deepening on the coast bringing off shore flow across the east side by Wednesday. This combination will bring temperatures to triple digits by Thursday in the west side valleys south of the Umpqua divide. On Thursday monsoonal moisture begins to move in from the south and have added a slight chance of thunderstorms in Northern California. The preceding southerly flow does not begin until Wednesday night, so the confidence that it will happen is not high. With a cut off low developing off shore of central California, the monsoonal moisture continues to wrap into our area Friday, bringing chances of thunderstorms into southern Oregon, but have kept just slight chances at this time. Sven && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning from noon to 9 PM PDT Sunday for ORZ624-625. CA...Red Flag Warning from noon to 9 PM PDT Sunday for CAZ285. Red Flag Warning until 9 PM PDT this evening for CAZ285. Pacific Coastal Waters...None. $$
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1002 PM EDT Sat Jul 7 2018 .SYNOPSIS... Tropical Depression Three will meander off the southeast coast for the next several days before moving off to the northeast by midweek. A trough of low pressure and weak front will move into the region mid to late week. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... As of 950 PM Sat...Latest radar returns continue to show bands of light rain showers coming ashore, while an isolate thunderstorm is over the Gulf Stream this evening. Slightly lowered PoPs based on current radar trends and latest HRRR model. The best chances for rain will continue over the coastal counties. No other changes to the public forecast. Pre Dis...The sfc analysis is showing high pressure to the north, while TD#3 is well to southeast of NC this evening, and will continue to spin and remain nearly stationary overnight. Occasional bands of rain showers will continue to rotate ashore through tonight for coastal areas where chance to likely PoPs are forecast through the night. The weak trough started to sink down into the Coastal Plains this evening and precip has dissipated over the inland area...therefore have made tweaks to PoPs over the Coastal Plains. Breezy conditions will continue as the gradient tightened between TD#3 and high pressure ridging into the Carolinas from the NW. Lows tonight near climo in the mid/upr 60s interior to low 70s coast. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... As of 330 PM Sat...TD3 will remain well to the SE with best moisture along the coast, though not as much covg as Sat and therefore just advertising sct/iso pops for eastern 2/3 of the FA, with dry conditions interior. It will continue breezy, especially along the coast with tightened gradient between TD3 and high pres ridging into the Carolinas. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... As of 330 AM Sat...Main feature through mid week will be TD 3, which is forecast to slowly meander off the SE coast. Sunday through Tuesday...TD 3 is forecast to strengthen and slowly meander off the SE coast into Monday before finally lifting NE Tuesday. Some uncertainty remains regarding the intensity of the system and exact track, which will impact the forecast specifics. It still looks like the system will remain far enough east to keep the strongest winds well off the coast, though a jog to the west and areas along the immediate coast could see some stronger wind gusts develop. Most models keep the system well offshore, though the NAM/HWRF/UKMET/CMC bring it closer to the NC coast. At this time it still looks like the main impacts from TD 3 will limited to areas along the immediate coast. Expect an enhanced rip current threat this weekend into early next week, as well as rough surf for the beaches. Some ocean overwash and minor erosion will be possible for the Outer Banks. Interested parties should continue to monitor this system over the next few days. Highs in the low to mid 80s Sunday, warming a few degrees Monday and Tuesday. Could see isolated to scattered showers along the coast in the outer rainbands, and will keep sc to low chance pops. Wednesday through Friday...TD is forecast to lift quickly NE Tuesday night and Wed, along with any lingering impacts. Upper trough moves into the area, and models try to show a weak front pushing into the area Thursday. Increasing precip chances and will keep sc to low chance pops. Temps near climo through the period, in the upper 80s to low 90s. Models also trying to show lingering Beryl lifting well offshore of the SE coast Thu and Fri, which could lead to additional rip current concerns for the beaches. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Short Term /through 18Z Sunday/... As of 715 PM Sat...High confidence of a mix of VFR and MVFR conditions for the TAF period. Expect MVFR conditions to persistent over the coastal TAF sites (KEWN/KOAJ) as there is plenty of moisture over the area on the outer periphery of Tropical Depression #3, while inland TAF sites (KPGV/KISO) will see mainly VFR, but cannot rule out an occasional MVFR ceiling to stream by overnight. Winds will remain gusty through tomorrow as pressure gradient is tightened. Expect additional showers over the coastal TAF sites tomorrow and MVFR ceilings condition spreading to the inland TAF sites after 12z Sun. Long Term /Sunday night through Wednesday/... As of 330 AM Sat...Sub-VFR conditions could lingering into early Sun, then improving to pred VFR through mid week. && .MARINE... Short Term /through Sunday/... As of 950 PM Sat...A tight pressure gradient remains over the portions of the coastal waters this evening as high pressure from the north and TD#3 remains to the southeast of NC. This resulted in persistent gusty winds up to 40kt mostly over the Sounds, Alligator RVR and north of Cape Hatteras...therefore have upgraded those zones to a Gale Warning until 4 am Sun. The SCA for the rest of the coastal zones remain unchanged. Pre Dis...Only change to the SCA was to add Neuse river to the headline, and adjusted ending times of the SCA for the waters per latest NWPS. Tightened gradient will persist between TD3 well off the NC coast and high pres riding in from the N and NW. Winds will be a solid 20-30 kt with ocnl gusts to gale force, with highest winds across the sounds and nrn waters. Trop Depression Three to the SE and high pres to the N. Seas will build to 6 to 9 feet for the northern waters, and therefore issued high surf adv for areas north of Oregon Inlet. Seas further south into the 4 to 7 ft range. Long Term /Sunday night through Wednesday/... As of 330 AM Sat...The main feature late weekend into early next week will be TD 3, which is forecast to slowly meander off the SE coast. Current NHC track shows TD strengthening, then lingering off the SE coast into Monday before finally lifting NE Tuesday. Some uncertainty remains regarding the intensity of the system and exact track, which will impact the forecast specifics. It still looks like the system will remain far enough east to keep the strongest winds out of our waters, though a slight jog to the west and coastal waters could see TS force wind gusts. SCAs currently out for the waters and sounds through early next week, and may need to be extended depending on how the TD evolves. Gusty NE winds will continue Sunday, 15-25 kt, diminishing to 15-20 kt Mon. Seas will peak at 5-8 ft north of Hatteras Sunday, and 4-7 ft south diminishing about a foot or so Monday. Winds become more S/SW late Tue and Wed with seas slowly subsiding. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...Beach Hazards Statement through Sunday evening for NCZ103. High Surf Advisory until 8 PM EDT Sunday for NCZ103. MARINE...Small Craft Advisory until midnight EDT Sunday night for AMZ137. Gale Warning until 4 AM EDT Sunday for AMZ130-131-135-150-152. Small Craft Advisory until 5 PM EDT Monday for AMZ154. Small Craft Advisory until 7 AM EDT Monday for AMZ156-158. && $$ SYNOPSIS...TL NEAR TERM...TL/BM SHORT TERM...TL LONG TERM...CQD AVIATION...CQD/BM/MS MARINE...CQD/TL/BM
Area Forecast Discussion
National Weather Service Nashville TN
833 PM CDT Sat Jul 7 2018 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... Latest radar imagery this evening shows widely scattered showers and storms continued in an arc from our southern counties northeastward into the Upper Cumberland. Have adjusted pops for the evening based on radar. After midnight, HRRR suggests a few showers will remain possible over southern zones so will keep a slight chance pop going for there, but will go dry everywhere else. Also added mention of patchy fog over the south and east where today`s rainfall will likely lead to some fog formation overnight. Otherwise, forecast appears to be on track with only a few other minor tweaks. && .AVIATION... 00Z TAF DISCUSSION. While cigs may dip into the 3kft to 5kft this evening as diminishing showers and storms pass over CSV, BNA, and MQY, expect mostly VFR conditions throughout tonight. Clouds will increase on Sunday morning as winds turn out of the southeast. Afternoon showers are expected again with the best coverage over areas west of I-65. Included VCSH in the forecast for all sites after 18z. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Shamburger AVIATION........11
Area Forecast Discussion
National Weather Service Tallahassee FL
959 PM EDT Sat Jul 7 2018 .UPDATE... Modified PoPs somewhat across GA to account for line of weakening showers/storms along I75. HRRR has whats left of it possibly making it into the Albany area before dissipating so nudged chances up in this area through 06Z. After 06Z best PoP chances move offshore. Skies will be mostly cloudy overnight with lows in the low/mid 70s. && .PREV DISCUSSION [730 PM EDT]... .NEAR TERM [Through Tonight]... Scattered to numerous showers and thunderstorms are expected through the early evening hours before gradually diminishing. Storms will likely last the longest across the far northern portion of the forecast area. There still appears to be the threat for a few stronger storms to pulse up with gusty winds this afternoon and evening, mainly across portions of southern Georgia and southeast Alabama. Modifying the 12z KTAE sounding for afternoon T/Td of 90/73 yields SBCAPE values around 4000 j/kg. The mid level lapse rates are fairly steep for this time of year with the observed 700-500 mb lapse rate at 6.8 C/km. Overnight lows are expected to be in the low to mid 70s. .SHORT TERM [Sunday Through Monday Night]... In the upper levels a ridge will be over the Southeast. At the surface a weak pressure gradient will be over the region. A weak stationary boundary will be over the region on Sunday and Monday. Therefore showers and thunderstorms will be more widespread than a typical summer day. Convective activity will not be confined to the afternoon and evening hours. Although afternoon/evening will be the most active times. Daytime POPs will be 50 to 70 percent. Nighttime POPs will be 20 to 40 percent. Highs will be in the upper 80s and lower 90s. Lows will be in the lower 70s. .LONG TERM [Tuesday Through Saturday]... In the upper levels a ridge will be over the Southeast until an upper level low forms late in the week. At the surface a weak pressure gradient will be over the region until a weak low forms late in the week. Nighttime POPs will be 20 to 40 percent. Daytime POPs will be 40 to 60 percent, possibly higher late in the week as low pressure develops. Highs will be in the lower 90s. Lows will be in the lower 70s. .AVIATION [Through 00Z Monday]... An overall decreasing trend is expected with thunderstorm activity over the next several hours. Overnight, VFR conds should prevail into the early morning hours. Diurnal CU will develop by mid morning with bases 025-030. Thunderstorm development will occur by late morning with scattered coverage across the Tri-State region into the afternoon. .MARINE... Light winds will be southerly through the weekend. Light winds will be northerly early this week. Seas will be low around 1 to 2 feet. .FIRE WEATHER... Other than low dispersions Sunday, no fire weather conditions are expected. Chances for wetting rains will remain high through much of the next week. .HYDROLOGY... The wet weather continues through this week. Local rivers are steady and below action stage at this time. QPF is 1 to 2 inches over the next week. Higher rain totals locally are possible. Ponding of water on roadways and flooding of low lying areas is possible with heavier downpours. .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 71 90 73 92 74 / 30 70 30 50 20 Panama City 74 88 75 90 76 / 40 50 20 50 30 Dothan 72 88 72 90 73 / 40 60 30 60 30 Albany 73 90 74 91 74 / 60 60 40 60 20 Valdosta 71 90 73 90 73 / 40 70 40 60 20 Cross City 72 91 73 91 73 / 30 50 20 40 30 Apalachicola 75 87 75 89 77 / 40 40 20 40 20 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ UPDATE...Scholl NEAR TERM...DVD SHORT TERM...McD LONG TERM...McD AVIATION...Scholl MARINE...McD FIRE WEATHER...Scholl HYDROLOGY...McD
Area Forecast Discussion
National Weather Service Tucson AZ
141 PM MST Sat Jul 7 2018 .SYNOPSIS...Deeper moisture will bring a significant upswing in showers and thunderstorms this weekend into next week. Daytime temperatures will be above normal this weekend then be generally below normal next week. && .DISCUSSION...Not much change in thinking from this morning`s discussion, with the upper high centered just north of the four corners region over west central Colorado and the upper ridge oriented from southwest to northeast across the desert southwest and into the central high plains. The first cells developed today around 19Z and were along the Rim and over portions of central Pima County. At this time just very isolated activity, although models continue to show isolated to scattered activity as we work through the remainder of afternoon and into the evening hours tonight. The 18Z HRRR and the UofA AZ WRF-NAM/WRF-GFS all indicate the favored area of development along the Rim, with this activity then pushing to the southwest. A weak disturbance over far west central New Mexico (as seen on the Goes-16 Mid Level Water Vapor Channel 9 (6.95um)) is expected to enhance development as it works into the region later today. The high center will remain quasi-stationary over the next 36-48 hours, as the upper ridge becomes more amplified across the western United States. As this takes place, mid level flow will switch from a east/northeast direction today to a east/southeast direction by Monday. This subtle change in the flow pattern will allow for deeper moisture to work into the area as model PW values near 1.5" on Monday. The models all begin to ramp up activity on Sunday, but especially so in the Monday through Wednesday time frame. At this time have scattered pops in the valleys for Sunday, with scattered to numerous pops in the mountains. SPC has highlighted a good chunk of the forecast area on Sunday as Marginal Risk, with isolated severe thunderstorms possible and the main threat being strong wind gusts. Expect high end scattered valley pops Monday through Wednesday, with numerous showers and thunderstorms in the mountains. Deterministic model guidance numbers are indicating that the convective activity early to mid next week will occur during the late afternoon and especially the evening/late night hours. By late next week, expect a typical monsoon forecast with scattered afternoon and evening showers and thunderstorms, mainly from Tucson eastward. Daytime temperatures will be a couple of degrees above normal through Sunday, before lowering to below normal values most of next week due to deeper moisture and increased cloud cover. && .AVIATION...Valid through 09/00Z. Isolated to scattered -TSRA/-SHRA with strong gusty outflows possible this afternoon/evening as well as Sunday morning/afternoon. Due to the isolated nature of the storms today, have not included -TSRA/-SHRA in the TAFs, however ammendments may be needed later in the day. This afternoon and evening expect SCT to locally BKN clouds at 8k-12k ft AGL with SCT-BKN layer above 20k ft AGL. Ceilings could be MVFR near any storms. Outside of thunderstorm winds, SFC winds will be out of the east/southeast at 8-15 kts with some afternoon gusts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Moisture will continue to increase resulting in significant increases in Min and Max RH values and thunderstorm coverage. From Sunday onward we are expecting more numerous thunderstorms and showers across the entire area including occasional rounds of nighttime storms. Mainly for the first few days, the rain cores will be smaller with dry lightning around the periphery of the storms. Typical storm motion will be toward the west or southwest. 20 ft surface winds will generally be 15 mph or less from an easterly direction through midweek, and thereafter follow a more typical diurnal pattern. In the vicinity of thunderstorms expect strong and variable winds. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Discussion...Zell Aviation/Fire Weather...Hardin Visit us on Facebook...Twitter...YouTube...and at