Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/12/16

Area Forecast Discussion...UPDATED
National Weather Service Flagstaff AZ
853 PM MST SAT JUN 11 2016

.SYNOPSIS...Isolated showers will continue over northern
Coconino county through Saturday evening. Otherwise...dry and breezy
conditions are forecast Sunday, with a slight chance of
thunderstorms north of I-40 on Monday. A drying/warming trend will
commence Tuesday, and will continue through the end of next weekend.

&&

.DISCUSSION...Convection is rapidly decreasing this evening...with
isolated showers expected til midnight over N. Coconin county. Grids
are in great shape, and no updates are planned at this time.

&&

.PREV DISCUSSION.../323pm mst/...Isolated to scattered thunderstorms
continue to develop over northern Yavapai and western Coconino
counties where MUCAPE values are ranging between 1000-1500 J/kg.
However, weak deep layer shear is keeping this convection
disorganized and well below severe limits. This activity should
continue through the late afternoon hours, then begin to wane around
sunset with the loss of daytime heating.

By Sunday, an upper level trough will sag just west of the Baja
Peninsula. Models prog Arizona to get dry slotted with little to no
convection anticipated. However, given the proximity of the trough
and subsequent height gradient, breezy to windy conditions are
forecast over northern Arizona. Winds should remain below advisory
levels.

Monday, the aforementioned trough will weaken as it lifts north over
Arizona. The best upper forcing should remain confined to areas
north of I-40. Upper dynamics (albeit weak) combined with lingering
moisture and instability should be sufficient to warrant a slight
chance of Monday afternoon thunderstorms north of I-40.

Tuesday through Saturday, an upper level ridge will build over the
southwestern United States. This will lead to a drying and warming
trend over Arizona through next weekend (June 19).

&&

.AVIATION...For the 06Z Package...VFR conditions expected through
Sunday...with southerly winds gusting to 30kts Sunday afternoon.
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Showers and thunderstorms will diminish this
evening around sunset. On Sunday drier air moves in ending chances
for thunderstorm activity while southwest 20FT winds will increase
to a sustained 15 to 20 mph range. Monday a few isolated showers
possible along and north of Interstate 40.

Tuesday through Thursday...High pressure builds in from Tuesday
onward with hot and dry weather in the extended forecast.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...TM/BAK
AVIATION/FIRE WEATHER...Bohlin/BAK

For Northern Arizona weather information visit
weather.gov/flagstaff



  [top] Area Forecast Discussion National Weather Service Tucson AZ 330 PM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Scattered showers and thunderstorms were ongoing mostly north-to-east of the Tucson metro area this afternoon. Various 11/12Z NWP models suggest the bulk of these showers and thunderstorms will gradually decrease in coverage and intensity during the next several hours. Expect isolated to scattered showers and thunderstorms mainly from Tucson east to the New Mexico border this evening. A slight chance of showers and thunderstorms then continues late tonight into Sunday evening mainly near the New Mexico border. 11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity nwd/ewd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight thru Sunday afternoon. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson northward, and eastward to the New Mexico border. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 323 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION/FIRE WEATHER...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 308 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend (June 19). && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
  [top] Area Forecast Discussion National Weather Service Phoenix AZ 224 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next several days resulting in somewhat cooler weather through early next week. Showers and thunderstorms will also be pushed well east as drier air moves back into the region. After several relatively comfortable days with near normal temperatures through the middle of next week, excessively hot weather will likely settle back into the area by the end of next week. && .DISCUSSION... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Isolated showers and thunderstorms should only impact areas south of the Phoenix metro through the rest of the afternoon, but confidence is not high enough to totally rule a shower or storm to briefly affect southern portions of the metro area. Breezy southerly winds will eventually turn westerly this evening for the Phoenix terminals and remain westerly through much of the overnight. After midnight the area will be under drying conditions and clearing skies. Gusty southerly winds will affect southeast California including KBLH and KIPL through around midnight with winds 10 kts or less thereafter. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Nolte/MO AVIATION...Kuhlman FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Flagstaff AZ 1218 PM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Convection is firing over the higher terrain of Yavapai county and western Coconino county early this afternoon. Thunderstorm activity is also developing over southern Apache county in the vicinity of the White Mountains. Think the convection over Yavapai/western Coconino counties will expand in coverage this afternoon due to increasing instability. Updated the forecast to expand scattered coverage of afternoon thunderstorms into the North Rim area based on current obs/trends. The remaining weather elements are in good shape. The updated forecast has been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with scattered coverage over Yavapai and western Coconino counties. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 935 AM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Current visible satellite imagery shows convective clouds beginning to develop over Yavapai and western Coconino counties. Furthermore, a mid/high level cloud deck over most of Navajo and all of Apache counties should continue to lift north of the region through the afternoon. The latest high-res models prog increasing instability over Yavapai and western Coconino counties today. Furthermore, with dewpoints in the upper 40s and 50s, think enough lift and instability should initiate convection along the Mogollon Rim this afternoon. Weak deep layer shear should keep convection below severe limits. Updated the forecast based on current obs/trends. Increased the temporal resolution of pops in order to try and best time the convection across northern Arizona this afternoon. Otherwise, the remaining forecast is on track. The updated products have been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with isolated coverage in northwestern Arizona and more scattered coverage in northeastern Arizona. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. High pressure builds in from Tuesday onward with hot and dry weather. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 915 AM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...11/12Z Univ of AZ WRF-NAM and several HRRR solutions suggest that showers/tstms will develop near the Tucson metro area eastward/southward later this morning into early this afternoon. These cells will then move quickly nwd/newd, with the main concern for potentially damaging wind gusts. The bulk of these showers/ tstms will end this evening. There are no updates planned at this time. Please refer to the additional sections for further detail. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity ewd/swd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight into Sunday morning. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson east and south. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through Friday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next Friday. && .PREV DISCUSSION /234 AM MST/...Precipitable water values remain well above mid-June normals this morning with values mostly in the 1.00"-1.50" range. Water vapor imagery showed an upper level low approaching southern CA. Drier air will start to push in from the west as the day progresses, but enough will be around across the eastern 2/3rds of the area for isolated valley/scattered mountains showers and thunderstorms. Precipitable water values are forecast to be below 1" on Sunday with a slight chance of storms relegated to the White mountains. High temperatures this weekend will remain several degrees below normal. Upper level trof will push across the state on Monday providing slightly cooler daytime temperatures and further drying of the atmosphere. Upper ridge strengthens over the area Tuesday through Friday resulting in warmer daytime high temperatures. Outside of this forecast package are likely hotter daytime temperatures as the upper ridge continues to strengthen over the area. Highs next weekend could rival what occurred earlier this month. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
647 AM EDT FRI JUN 10 2016 .SYNOPSIS... Issued at 356 AM EDT Fri Jun 10 2016 Showers and thunderstorms are possible through the weekend. Temperatures this afternoon will rise into the upper 80s and low 90s. Lows tonight will be in the upper 60s and low 70s. Otherwise, expect a cold front to bring additional chances for showers and storms late Saturday afternoon into Sunday morning. A few isolated strong to severe storms are possible with this front, though confidence at this point is low. Stay tuned to the latest forecasts for updates. && .SHORT TERM...(Today and Tonight) Issued at 356 AM EDT Fri Jun 10 2016 Showers and thunderstorms continue through the early morning, primarily from I 69 westward. At 4 am EDT an area of showers and storms were slowly shifting southeastward from near Lake Michigan into Cass/Miami/Wabash county. These showers/storms are supported by an area of decent upper level divergence, strong moisture transport and elevated instability. Models of course are in disagreement over the coverage of precipitation further northeast as we head through the morning, however are consistent in showing the area of precipitation now present shifting southeastward. Have numerous showers and thunderstorms in these areas through early morning, dissipating from northwest to southeast, and scattered to isolated showers/storms possible elsewhere. Otherwise, the forecast for this afternoon and tonight will be tricky, with our area lodged on the eastern periphery of an upper level ridge. Chances for precipitation this afternoon will be dependent on the weak short wave passing through the flow aloft. Moisture is certainly abundant this go around, with PWATs up around 1.7 inches-which is about 150 percent of normal. Kept fairly consistent with the previous forecast. With collocated better moisture/weak support from 500mb shortwave and stronger afternoon instability in the 1500-2000 J/Kg range, kept chances for showers and storms in the east during the afternoon. As far as severe threat goes, with limited shear-around 25 knots towards the afternoon hours it looks to be isolated if anything. SPC has us in a marginal risk, which is appropriate given the higher instability that will be present. One thing is for certain...with 850mb temps of 17-18C, high temperatures will climb into the upper 80s and low 90s-especially in the west/southwest where cloud cover diminishes earlier. Flow tonight will be zonal, with a slight chance for showers and storms, mainly north of I 80-90, associated with a weak shortwave. Confidence in this occurring is low, however. && .LONG TERM...(Saturday through Thursday) Issued at 356 AM EDT Fri Jun 10 2016 We start out the long term forecast on Saturday with another weak shortwave that gets somewhat washed out as the upper level ridge over the plains builds. The best chances for showers and storms would be with the sfc cold front expanding southeastward from Michigan late Saturday afternoon into Sunday morning. With support from the frontal boundary, instability up to 1500-2500 J/KG, and 0-6 KM Bulk shear to 30 Kts isolated severe weather is a possibility. SPC has areas north of US 30 in a slight risk for severe weather, though there is low confidence given the variability in the models. For now stuck with chance of showers and t-storms through the late afternoon/evening hours. Sunday will likely be dry with the cold front sagging south of our area and surface high pressure/strong ridge building aloft. Temperatures will be relatively cooler in the CAA behind the front, with highs in the mid-upper 70s near Lake Michigan to the 80s inland. The forecast becomes fairly murky as we head into the extended period. Monday we are again on the eastern fringes of the upper level ridge. Low pressure to the west is forecast to lift a warm front into the area Monday morning where it eventually becomes stationary and lingers through Thursday. This is when the surface low/upper level trough over WI takes a dive into our area and lingers through Friday night. With widely varying model solutions kept steady with the consensus blend from Monday onward-which brings mostly chance pops into our area. && .AVIATION...(For the 12Z TAFS through 12Z Saturday Morning) Issued at 647 AM EDT Fri Jun 10 2016 Vfr conds xpcd through the pd. Current conv cluster driving sewd alg ern edge of ll theta-e gradient and will largely bypass KFWA terminal erly on although ern bound of stratiform rain shield may expand far enough east yet to provide for a brief pd of mvfr vsby restriction through abt 14Z. Upstream convn ovr se WI conts to wkn in conjunction to wkng llj yet xpc any lingering leftovers to fizzle nwwd of the terminal. That leads to qn of what if anything redvlps this aftn alg tail end of current complex aligned w/modest mass flux arising within renewed llj. Ltl doubt conds will destabilize sigly esp invof the highway 30 corridor by lt aftn yet may be end up being capped in reflection of upstream warming noted in 00Z KDVN raob. Will await 12Z data to see if that scenario holds water. && .IWX Watches/Warnings/Advisories... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...MCD SHORT TERM...MCD LONG TERM...MCD AVIATION...T Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
Area Forecast Discussion National Weather Service Indianapolis IN 632 AM EDT FRI JUN 10 2016 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 342 AM EDT FRI Jun 9 2016 A thunderstorms complex will move across northeast portions of central Indiana this morning as a warm front over northern Indiana and Ohio moves north into the great lakes. Hot and dry weather will occur Saturday as a strong upper ridge of high pressure builds into the Mississippi valley. The frontal system over the great lakes will drift south across our region Sunday and then meander around. Thunderstorms chances will increase after the weekend as an upper disturbance moves our way. && .NEAR TERM /Today/... Issued at 342 AM EDT FRI Jun 9 2016 Radar indicates an area of showers and thunderstorms around the Chicago area and northwest Indiana. These thunderstorms will drift southeast across northern Indiana and move into the northeast part of our region by day break. Will go with likely POPS east of a Kokomo to Rushville line and chance POPS along and east of a Lafayette to Indy line. Otherwise...it will remain dry across the southwest half of our region this morning. Rapid refresh model indicates numerous thunderstorms over northeast and east central sections for a few hours this morning and then the storms should diminish as the warm front lifts to the northeast. Will continue slight chance POPS over the eastern half of our region this afternoon...although confidence is low. There will be more sun this afternoon and highs should range from the lower 90s over western sections to the middle and upper 80s east. With afternoon sun and warm advection went a degree or two above a MOS blend on temperatures. && .SHORT TERM /Tonight through Sunday/... Issued at 342 AM EDT FRI Jun 9 2016 Models are in generally good agreement on the main features...but there are some differences on QPF. Will use a blend in most cases. An upper ridge of high pressure will build our way as the warm front moves north into the great lakes. Models indicate that we will be capped and expect mostly clear skies through Saturday. 850 MB temperatures will rise into the lower 20s and this will result in the hottest temperatures so far this season with highs in the lower 90s Saturday. The frontal system over the great lakes will drift south across our region late Saturday night and Sunday per models as an upper trough deepens along the New England coast. The NAM...GFS and GEMNH model shows some QPF with this front...while EURO is mostly dry. Will go with 20-30 percent POPS over north and central sections later Saturday night and most areas Sunday. Drier air behind the front will spread into northern areas Sunday afternoon and over most other areas Sunday night. Will end the thunderstorm chances upon arrival of this drier air. The NAM and GFS indicate some cooling over north and central sections Sunday...while the EURO is much less. Will go with a blend with temperatures a few degrees above a MOS blend...but not quite as warm as the EURO. Went with highs from the middle and upper 80s northeast Sunday to the lower 90s southwest. Lows will be from 65 to 70 tonight...lower 70s Saturday night and from 60 northeast to 70 southwest Sunday night. && .LONG TERM /Monday through Thursday/... Issued at 226 AM EDT Fri Jun 10 2016 The long term looks active with an upper ridge breaking down as several upper waves move southeast along it and into central Indiana. Highs start out in the 90s on Monday but decrease a bit thereafter as the ridge breaks down. For Monday and Monday night PoPs in the chance category are expected in the north with only a slight chance in the south as the ridge gets depressed from the north. Chances for thunderstorms then continue through the rest of the extended period and temperatures drop to the middle 80s for much of the week before cooler air from an upper low moving across the northern part of the country arrives to end the week. Models show differences in timing of the aforementioned shortwaves so nothing to key in on to designate any day as a dry one and thus made no substantive changes to the initialization. With ample heat and available moisture carried thunder each day. && .AVIATION /Discussion for 101200z TAF issuance/... Issued at 621 AM EDT Fri Jun 10 2016 An upper wave moving through along a surface front is producing showers and thunderstorms across northern and parts of central Indiana this morning. This activity has stayed east of the sites thus far, but latest radar loop indicates KLAF could see a shower or storm directly impact there during the first hour or two of the forecast period. At KIND HRRR looks like development could bring some restrictions to KIND from visibilities within thunderstorms but radar loop doesn`t match this scenario as well. However starting to see outflow boundary that could encourage more development in this direction. Therefore will include a tempo TSRA at KLAF but with less confidence will stick with VCTS at KIND. Ceilings should be at or above 5 kft. After storms move out later this morning expect conditions to remain VFR through the rest of the period. && .IND Watches/Warnings/Advisories... NONE. && $$ SYNOPSIS...JH NEAR TERM...JH SHORT TERM...JH LONG TERM....CP AVIATION...CP
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
122 AM EDT FRI JUN 10 2016 .SYNOPSIS... Issued at 306 PM EDT Thu Jun 9 2016 Warmer and more humid air will build over the region through Saturday as a warm front lifts northeast. This front will bring increasing chances for showers and thunderstorms tonight into Friday morning. Low chances for additional storms will continue into Friday afternoon and Saturday. Lows tonight will range from around 60 to the upper 60s. Highs Friday and Saturday will range from the mid 80s to lower 90s. Heat indices both days will be around 90 to the mid 90s. && .UPDATE... Issued at 916 PM EDT Thu Jun 9 2016 Widely scattered showers continue to develop over the past hour or 2 generally from Michigan City to Warsaw where earlier light rain has allowed for rapid moistening of the column...depicted by quick jump in dewpoints into the lower 60s. Effective warm front still residing well southwest of the area from eastern Iowa across central Illinois to south of Lafayette with current/past shower/storm activity helping slow progress of the front for the moment. Convection has quickly developed over the last hour or so across southern WI/northern IL on nose of modest low level jet and pocket of 2000 j/kg of CAPE. One cell went up and became marginally severe but quickly collapsed on itself despite somewhat favorable shear. As these cell are dropping southeast the appear to weaken as they move away from the pocket of better instability. This causes concerns with regards to SE extent over time into the area. Have to make some changes to the grids...at least through 6z and maybe beyond to shift focus more southwest. Don`t want to get too carried awat with everything still evolving...but HRRR has consistently kept better chances for precip in SW areas with more sct in nature NE. Will do best to capture trends in grids but more updates likely. && .SHORT TERM...(This Evening through Friday) Issued at 249 PM EDT Thu Jun 9 2016 Thunderstorm initiation and evolution remain primary concern in the short term period for tonight and Friday. Models continue to indicate thunderstorm development this evening near a northwest to southeast oriented warm front which will slowly lift northeast. This boundary will be quasi stationary tonight into Friday as low level jet increases tonight along with theta-e surge and a weak short wave in northwest flow aloft. 12z model runs have continued prior trend of weaker forcing tonight but still initiate convection in same general area from WI to southern Lake Michigan. Complex expected to roll southeast along instability gradient near sfc front. Elevated instability is weaker as are mid level lapse rates. Better thermodynamics now arrive later tonight which will keep storms more in check. Still enough instability and modest 0-3km bulk shear of 25 to 30 knots to support a few strong storms and possibly a low end isolated severe storm...mainly in the northwest. Hail will be primary hazard and locally heavy rain possible with pwats increasing to over 1.5 inches but storms should be progressive. Rather stout low level inversion seen on soundings should limit wind gusts. Thunderstorms may linger in the east Friday morning before exiting the local area. Cloud debris likely early but should see sun mid to late morning with strong heating in the afternoon. Atmosphere looks capped with mid level heights rising. Cannot rule out isolated afternoon storms with any weak short wave but best chance per hires models appears to be in the east on fringe of increasing heights and thermal bubble. Still a low chance. High temps expected to recover to around 90 in the west and middle 80s east. Dew points will be on the rise...especially if we get decent rainfall tonight. This will make it feel much more humid than recent days. && .LONG TERM...(Friday Night through Thursday) Issued at 249 PM EDT Thu Jun 9 2016 Another convective complex looks likely Friday night along warm front which will have lifted north of our area. Depending on evolution this could clip our northern counties late Friday night. Residual cloud cover remains a concern for Saturday impacting high temps and degree of destabilization. We remain on edge of mid level plains ridge and expect subsidence and drier air to our west to help keep western areas mostly clear and eventually erode any remaining cloud cover central. Temps still expected to soar into lower and even mid 90s west with full sun. Eastern areas remain more in question and stayed a bit conservative there with high temps...still reaching upper 80s. Afternoon CAPE to approach 2500-3000 j/kg but shear remains rather poor with just 15 to 20 knots and no strong signal for forcing. There are some hints at a pre-frontal trough dropping south out of decaying MCS that depending on timing could set off some storms in the afternoon. Given degree of instability present...strong and isolated severe storms are possible conditional on trigger as seen in 4km NAM. Main synoptic cold front sags through Saturday night. Slightly cooler air to filter in...especially northeast. This front to mainly scour out low level moisture leaving dry but seasonably warm conditions for Sunday and Monday as mid level ridge builds in. Models then hinting toward a rex block pattern with upper low developing over the plains underneath ridge. This occurring as very strong low pressure stalls over Newfoundland. Plains low then drifts toward our area with another quasi stationary boundary situated west to east. This to provide additional tsra chances through much of next week. Models tend to perform poorly with these weak cutoff lows in the warm season so confidence low in the long term period. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 122 AM EDT Fri Jun 10 2016 Vfr conds xpcd going fwd. Hwvr expanding conv cluster alg nose of focused into se WI/far ne IL attm xpcd to shift ewd erly this morning and overspread the terminals w/a pd of mvfr restriction in tsra likely. While any sense of consensus amg CAMs solutions is certainly lacking...extrapolation of current activity bridges loosely w/latest HRRR and spc 4km wrf both of which were used for timing. Otrws aftn pd presents somewhat of a dichotomy as much of the nr term solution scope dvlps a fairly unstable airmass yet do not redvlp storms invof of stationary fntl zone which will no doubt be outflw augmented/anchored somewhat by erly morning activity. Will forego a mention at this point but cont to monitor morning conv evolution and nr term guidance trends. && .IWX Watches/Warnings/Advisories... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...Fisher SYNOPSIS...Skipper SHORT TERM...Lashley LONG TERM...Lashley AVIATION...T Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
623 PM CDT SAT JUN 11 2016 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Sunday) Issued at 325 PM CDT SAT JUN 11 2016 A weak MCV was moving across northwest Missouri this afternoon which formed from an earlier MCS over Iowa this morning. Short term high resolution models have been showing convection developing through the morning and afternoon in northeast and east central Kansas. Latest RUC soundings show a weak cap remaining in place through peak heating. Cumulus remains rather flat across the area this afternoon similar to previous afternoons. Upper level ridge remains in place across the Central Plains. Tonight expect the cumulus clouds to dissipate with the loss of heating with mostly clear skies expected. Lows tonight will be similar to last night with low to mid 70s common. Sunday models continue to show some mid level energy over northeast Oklahoma and southeast Kansas. There may be enough lift in the afternoon when atmosphere becomes uncapped for isolated thunderstorms to develop from southeast Kansas into Arkansas and will leave east central Kansas dry for now with model qpf clustering to the southeast of the cwa. Highs on Sunday will be similar to today with highs in the low to mid 90s. Heat indices will again approach 100 degrees across parts of the area on Sunday afternoon. .LONG TERM...(Sunday Night through Saturday) Issued at 325 PM CDT SAT JUN 11 2016 Sunday night through Tuesday, storm chances increase for much of the period. Late Sunday evening have gone with slight chance POPs over southern to western portions of the area as perhaps weak forcing may provide enough lift in a moist environment to cause a few showers and thunderstorms. The chance remains small at this point as the boundary layer will remain mostly capped off and a weak upper circulation advances into southern Missouri. Late Sunday, a storm complex develops over west central Nebraska along the nose of a LLJ and slowly works its way southeast into the forecast area by early morning into a less favorably sheared environment and an area of smaller scale shortwave ridging. During the day, remnant thunderstorm activity and an uncapped environment should lead to mostly cloudy conditions with a few thunderstorms possible over eastern portions of the forecast area where weak ridging will still be influencing the area but continuing to be suppressed as larger scale forcing advances from the west. Therefore, have left chance POPs over western portions of the forecast area into the afternoon on Monday. Tuesday night, a LLJ will likely aid in the development of thunderstorms over western KS and as storms grow upscale, another complex may develop and begin to advance into the north central Kansas and on into northeastern Kansas over night. Most long term guidance is generally in better agreement but still details seem to be in question such as exact positioning of the upper wave and strength of the upper wave as it moves out of the Central Rockies into the Central Plains. Previous runs have shown this wave to actually be a closed off low and more intense but that has been backed off at this point a bit and now the overall flow of the southern stream energy may be a bit weaker. Regardless, a more northerly track of the upper low seems to make sense based on current positioning just off the SoCal region. Depending on the actual strength of the upper trough feature, it seems to make sense that as the overnight MCS organizes out west and moves into western portions of the forecast area it could be sustained through the morning into the early afternoon hours as shear profiles increase to above 35kts, MUCAPE reaches to around 2,000 to 2,500 J/kg and mid- level lapse rates increase to at least conditional and probably up to around 7 C/km. Of course, some changes will likely occur between now and Tuesday as to how much severe potential we end up with, but at least some needed rain will likely fall over much of the area as the long term forecast looks mainly dry after this round of precip with possibly the exception of next Friday time frame as a frontogenetical response sets up on the backside of the wave previously mentioned as it transitions into a cut-off low eventually working back into portions of the Ohio and mid MS Valley regions before filling and transitioning into a frontal system over the East coast region. Temps cool back a bit into the mid and upper 80s by next weekend as more zonal flow sets up over the Northern into Central Plains. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 610 PM CDT SAT JUN 11 2016 VFR continues through forecast period. Clouds expected to increase late afternoon Sunday with winds backing to the south southeast at or just below 10 kts. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...53 LONG TERM...Drake AVIATION...Prieto
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
319 PM CDT FRI JUN 10 2016 .SHORT TERM...(This Evening through Saturday) Issued at 311 PM CDT FRI JUN 10 2016 Upper level ridge continues across the Central Plains this afternoon. Weak upper trough was filling across central and northeast Kansas this morning. Surface trough continues across the western high plains with axis of mid to upper 60s dewpoints across central and eastern Kansas. Afternoon cumulus has developed across the area and should be on the decrease toward sunset with the loss of heating. With little change in airmass since yesterday expect low temperatures from the upper 60s to mid 70s overnight. On Saturday, 850 mb temperatures warm a degree or two from today. Forecast soundings suggest mixing down from around 850 mb with highs mainly in the low to mid 90s. Afternoon dew points in the upper 60s to around 70 will yield heat indices in the upper 90s to around 100 degrees in the afternoon. With no forcing aloft or at the surface and soundings showing weak cap remaining in place Saturday afternoon, will keep the forecast dry. .LONG TERM...(Saturday Night through Friday) Issued at 311 PM CDT FRI JUN 10 2016 Last part of the weekend should remain dry and very warm with high temps still in the 90s and heat indices into the mid to upper 90s. Precip chances increase into Monday as and overnight complex of storms appears to form over west central Nebraska and slowly make its way near or into East Central Kansas by early morning. It will be pushed along by a weak boundary and without significant forcing aloft, the trend based on 12Z model data will be to decrease in intensity and whatever rain and thunderstorms are left. Storms may linger into the morning and early afternoon over the forecast area, so have maintained chance POPs over most of the area. It isn`t until the Tuesday time frame and overnight Wednesday that a tight compact upper low forms and undergoes cyclogenesis as split southern stream flow aloft ejects out of the Rockies into the Central Plains. Best indication at this time is that the forcing aloft will increase over western and northern portions of the forecast area giving the best chance to strong to perhaps severe storms. With indications that there will be a remnant EML in place, there could be more isolated activity. But with the upper low deepening quickly, steep lapse rates aloft with favorable shear, due to the upper low, could result in mostly a severe hail and wind threat. Again, still not highly confident in the overall set up or other forcing mechanisms such as a possible modified dryline mixing into the area. Also, guidance does vary too much at this time to be on the high end chance POPs. Rest of the week after this does look dry once again with perhaps slight chance POPs as the upper low essentially becomes cut off from the upper flow aloft and eventually fills over the Ohio River Valley. Meanwhile temps cool back to the mid to upper 80s by the end of the week as northeast flow sets up with surface high pressure in place. && .AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon) Issued at 1227 PM CDT FRI JUN 10 2016 VFR conditions are expected throughout the period. Winds will remain gusty through the afternoon with gusts 20-25 knots. Winds will increase by mid-morning tomorrow with sustained at 10-15 knots and a few gusts up to 20 knots at MHK. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...53 LONG TERM...Drake AVIATION...Baerg
Area Forecast Discussion National Weather Service Dodge City KS 235 PM CDT FRI JUN 10 2016 ...updated aviation section... .SHORT TERM...(Today and tonight) Issued at 234 AM CDT Fri Jun 10 2016 KDDC WSR-88D shows some thunderstorms early this morning across the southern zones. This activity was at the base of a very weak 500-hPa trof. This activity will diminish quickly through the early morning hours. The next shot at thunderstorms comes this afternoon and evening. Have low confidence in storms developing, since the main wave will be mainly to the E/SE. Have very low pops SE of a line from Elkhart to Liebenthal. The ARW and 4 km NAM do break out storms (in different locations though), while the NMMB is mostly dry. Again, only went with 15-20 pops. Severe weather is not expected. Otherwise, highs today will be in the 90s with lows in the 60s to around 70 for Saturday morning. .LONG TERM...(Saturday through Thursday) Issued at 234 AM CDT Fri Jun 10 2016 The forecast is dry through early Sunday. Decided to take out pops Saturday evening as not seeing a whole lot of opportunity for convection with a 590 dm high overhead. Pops do ramp up quickly late Sunday into Monday and Tuesday. A synoptic trof will begin to influence our region with dynamics aloft and low level lift along surface boundaries. Tuesday looks the most interesting per the ECMWF. The GFS was not used as the trof looks too progressive. It`s summer and systems move slow typically versus what the GFS indicates. The EC paints a severe weather picture Tuesday evening with 40-50 kt of bulk shear, 3000 J/kg of CAPE and a warm front. Very large hail would be a concern if supercells develop. In addition, conceptually, warm front isolated tornadoes could be possible as well if you take the model verbatim. All these small scale details will be hammered out in future runs, but last nights 00Z EC run looked interesting for Tuesday evening as well (in terms of a ramp up of significant severe weather across the Kansas prairie). Otherwise, temps through the extended will be Summer-like with highs in the 90s and lows in the upper 60s to lower 70s. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 233 PM CDT Fri Jun 10 2016 VFR category is expected during the course of this TAF peiod. There is a general lack of convergence and source of lift for any convection. Wind shear profiles support a period of boundary layer wind shear in central KS, and is indicated in the HYS TAF. && .PRELIMINARY POINT TEMPS/POPS... DDC 69 94 69 94 / 20 10 10 20 GCK 68 94 69 95 / 10 10 10 20 EHA 66 92 66 95 / 20 10 10 20 LBL 69 93 68 94 / 20 10 10 20 HYS 70 94 69 93 / 10 10 10 20 P28 70 93 71 94 / 20 10 10 10 && .DDC Watches/Warnings/Advisories...NONE. && $$ SHORT TERM...Sugden LONG TERM...Sugden AVIATION...Russell
Area Forecast Discussion National Weather Service Goodland KS 120 PM MDT FRI JUN 10 2016 .SHORT TERM...(This afternoon through Saturday) Issued at 120 PM MDT Fri Jun 10 2016 Early afternoon WV imagery and RAP analysis indicates ridging extending across Colorado with axis centered across our CWA. A shortwave trough is east of our CWA. At the surface low pressure is in place across eastern Colorado, with a secondary surface trough axis near McCook Nebraska extending southeast through our CWA. This afternoon-Tonight: Weak forcing and moisture is rotating into the rockies and has led to thunderstorm development across higher terrain in south central Colorado. Some hi res guidance indicates possible development and movement towards our western CWA, however if this happens it will coincide with loss of daytime heating/instability and confidence is low this would make it into our CWA (particularly considering the mean storm motion and weak flow aloft away from our CWA). Otherwise subsidence and a deep dry air mass will preclude local thunderstorm development this afternoon/evening. Relatively light winds and clear skies should support another night of good radiational cooling, so expect similar lows as last night (around 60F west to around 70F east). Saturday: Upper level ridge shifts east while trough deepens in this west. This may allow for a little more forcing to shift eastward into our CWA, and there will be good instability in place. Models are still indicating a very dry air mass in place, and most guidance keeps dry conditions in place locally. Only NMM/ARW supporting isolated thunderstorm activity Saturday afternoon. I kept forecast dry for now, though I couldn`t rule of a stray elevated thunderstorm. As the surface trough shifts east and heights begin to fall, the air mass slowly "cools" over our CWA. Temps aloft projected by guidance are very similar to was was realized Thursday, and similar temperatures (low-mid 90s) would be anticipated. This is a little lower than today, but still above normal by 10-15 degrees. .LONG TERM...(Monday through Friday Issued at 218 AM MDT Fri Jun 10 2016 Temperatures on Monday will be a little bit cooler, but still remain slightly above normal as highs will reach into the middle to upper 80s. There will be a chance of precipitation on Monday and Tuesday as an area of low pressure, over the southwest U.S., looks to lifts out across the Rockies and Central High Plains as an open wave with a surface trough/front and pass over the forecast area. Temperatures on Tuesday will be cooler, lower to mid 80s, as a result. The rest of the week, expect dry and hot conditions to return to the Tri-State area as high pressure looks to influence the Central U.S. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1130 AM MDT Fri Jun 10 2016 VFR conditions will continue through the TAF period at KGLD and KMCK. Surface trough will remain in place near the CO state line with weak southerly gradient leading to winds below 12kt through the first 12hr of the TAF period. Gradient begins to increase by late morning Saturday, with gusts 20-30kt developing at KGLD at the end of the TAF period. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BW AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
257 AM CDT FRI JUN 10 2016 .SHORT TERM...(Today and Tonight) Issued at 255 AM CDT FRI JUN 10 2016 Southerly winds have helped keep overnight lows up into the middle 70s, although should still fall another few degrees before sunrise. With a warm start and mid level temps similar to yesterdays numbers, anticipating highs similar to Thursday with low to middle 90s from SE to NW. However dewpoints rise into the middle/upper 60s by the afternoon hours, and bump heat indicies into the middle/upper 90s. Weak upper trof out over the high plains on Thursday advances slightly eastward, but still not quite far enough east with the lift or to break the cap and bring precipitation into our area. For now only have an increase in cloud cover and will watch for progression. .LONG TERM...(Saturday through Thursday) Issued at 255 AM CDT FRI JUN 10 2016 On Saturday the upper ridge will be centered over the central US, while a remnant shortwave meanders close to the forecast area. At the moment the models depict this wave will be located east of the area as it rotates around the center of the high to the north. Most of the precipitation associated with this wave will occur over the Ozarks. Temperatures will not changed much with highs is the lower to mid 90s, and heat indices close to 100. On Sunday the upper high will begin to shift eastward over the Midwest. Meanwhile the longwave trough will progress into the Rockies. The models are keeping most of the area dry with not much forcing in place. Sunday evening a front over western NE will support the development of a storm complex that may progress along or near the KS/NE state line overnight. If this complex of storms moves across the area Monday morning clouds and lingering precip will effect the outcome for the afternoon. The models begin to disagree on how to handle the front, which is fairly weak, and show a shortwave trough lifting out over the plains Monday or Tuesday. There is uncertainty regarding any remnant outflows and or frontal positions. Ultimately cyclogenesis will support a surface low pressure to move across western and central KS either Monday or Tuesday due to timing differences. Instability could be very high ahead of this system, and the deep layer shear will increase due to the wave. By Thursday the shortwave will cut off from the main flow and meander somewhere over the MS valley. Precipitation from this wave could affect the area, but models will likely struggle with this cut off system so uncertainty is high. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 1158 PM CDT THU JUN 9 2016 For the 06z TAFs, VFR conditions are expected through the period. Some models still suggest that there may be a slight chance for some marginal LLWS overnight, however confidence is not high enough to warrant a mention in the TAFs at this time. Expect the southerly winds to increase once again by late Friday morning, with gusts around 20kts through the afternoon. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...67 LONG TERM...Sanders AVIATION...Hennecke
Area Forecast Discussion National Weather Service Dodge City KS 234 AM CDT FRI JUN 10 2016 ...updated short and long... .SHORT TERM...(Today and tonight) Issued at 234 AM CDT Fri Jun 10 2016 KDDC WSR-88D shows some thunderstorms early this morning across the southern zones. This activity was at the base of a very weak 500-hPa trof. This activity will diminish quickly through the early morning hours. The next shot at thunderstorms comes this afternoon and evening. Have low confidence in storms developing, since the main wave will be mainly to the E/SE. Have very low pops SE of a line from Elkhart to Liebenthal. The ARW and 4 km NAM do break out storms (in different locations though), while the NMMB is mostly dry. Again, only went with 15-20 pops. Severe weather is not expected. Otherwise, highs today will be in the 90s with lows in the 60s to around 70 for Saturday morning. .LONG TERM...(Saturday through Thursday) Issued at 234 AM CDT Fri Jun 10 2016 The forecast is dry through early Sunday. Decided to take out pops Saturday evening as not seeing a whole lot of opportunity for convection with a 590 dm high overhead. Pops do ramp up quickly late Sunday into Monday and Tuesday. A synoptic trof will begin to influence our region with dynamics aloft and low level lift along surface boundaries. Tuesday looks the most interesting per the ECMWF. The GFS was not used as the trof looks too progressive. It`s summer and systems move slow typically versus what the GFS indicates. The EC paints a severe weather picture Tuesday evening with 40-50 kt of bulk shear, 3000 J/kg of CAPE and a warm front. Very large hail would be a concern if supercells develop. In addition, conceptually, warm front isolated tornadoes could be possible as well if you take the model verbatim. All these small scale details will be hammered out in future runs, but last nights 00Z EC run looked interesting for Tuesday evening as well (in terms of a ramp up of significant severe weather across the Kansas prairie). Otherwise, temps through the extended will be Summer-like with highs in the 90s and lows in the upper 60s to lower 70s. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1200 AM CDT Fri Jun 10 2016 Convection across SW Kansas is diminishing and will watch radar trends to see if an amendment is needed at each terminal. Otherwise, VFR conditions will prevail. There could be convection once again tomorrow afternoon and evening, but latest guidance suggests this probably won`t impact the terminals. Will leave out for now. Winds will be SE/S 10-15 kt increasing 15-25 kt by late morning through dusk. && .PRELIMINARY POINT TEMPS/POPS... DDC 93 69 92 69 / 20 20 10 10 GCK 96 68 93 68 / 10 10 10 10 EHA 93 65 90 65 / 20 20 10 10 LBL 94 68 92 67 / 20 20 10 10 HYS 95 70 94 70 / 10 10 10 10 P28 95 71 93 72 / 10 20 10 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Sugden LONG TERM...Sugden AVIATION...Sugden
Area Forecast Discussion National Weather Service Dodge City KS 234 AM CDT FRI JUN 10 2016 ...updated short and long... .SHORT TERM...(Today and tonight) Issued at 234 AM CDT Fri Jun 10 2016 KDDC WSR-88D shows some thunderstorms early this morning across the southern zones. This activity was at the base of a very weak 500-hPa trof. This activity will diminish quickly through the early morning hours. The next shot at thunderstorms comes this afternoon and evening. Have low confidence in storms developing, since the main wave will be mainly to the E/SE. Have very low pops SE of a line from Elkhart to Liebenthal. The ARW and 4 km NAM do break out storms (in different locations though), while the NMMB is mostly dry. Again, only went with 15-20 pops. Severe weather is not expected. Otherwise, highs today will be in the 90s with lows in the 60s to around 70 for Saturday morning. .LONG TERM...(Saturday through Thursday) Issued at 234 AM CDT Fri Jun 10 2016 The forecast is dry through early Sunday. Decided to take out pops Saturday evening as not seeing a whole lot of opportunity for convection with a 590 dm high overhead. Pops do ramp up quickly late Sunday into Monday and Tuesday. A synoptic trof will begin to influence our region with dynamics aloft and low level lift along surface boundaries. Tuesday looks the most interesting per the ECMWF. The GFS was not used as the trof looks too progressive. It`s summer and systems move slow typically versus what the GFS indicates. The EC paints a severe weather picture Tuesday evening with 40-50 kt of bulk shear, 3000 J/kg of CAPE and a warm front. Very large hail would be a concern if supercells develop. In addition, conceptually, warm front isolated tornadoes could be possible as well if you take the model verbatim. All these small scale details will be hammered out in future runs, but last nights 00Z EC run looked interesting for Tuesday evening as well (in terms of a ramp up of significant severe weather across the Kansas prairie). Otherwise, temps through the extended will be Summer-like with highs in the 90s and lows in the upper 60s to lower 70s. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1200 AM CDT Fri Jun 10 2016 Convection across SW Kansas is diminishing and will watch radar trends to see if an amendment is needed at each terminal. Otherwise, VFR conditions will prevail. There could be convection once again tomorrow afternoon and evening, but latest guidance suggests this probably won`t impact the terminals. Will leave out for now. Winds will be SE/S 10-15 kt increasing 15-25 kt by late morning through dusk. && .PRELIMINARY POINT TEMPS/POPS... DDC 93 69 92 69 / 20 20 10 10 GCK 96 68 93 68 / 10 10 10 10 EHA 93 65 90 65 / 20 20 10 10 LBL 94 68 92 67 / 20 20 10 10 HYS 95 70 94 70 / 10 10 10 10 P28 95 71 93 72 / 10 20 10 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Sugden LONG TERM...Sugden AVIATION...Sugden
Area Forecast Discussion National Weather Service Goodland KS 1135 PM MDT THU JUN 9 2016 .SHORT TERM...(This evening through Friday) Issued at 201 PM MDT Thu Jun 9 2016 Early afternoon WV satellite imagery and RAP analysis shows upper level ridging across the SW US. A shortwave trough is currently centered over western KS with a weaker shortwave rotating over eastern KS. At the surface a surface trough is approximately along the CO/KS border extending into SW Nebraska, with SW flow across SW Kansas into south central Nebraska. This afternoon-evening: with forcing associated with shortwave trough lingering potential exists for thunderstorm development. Main CAPE axis is associated with moist surface layer in SW flow with marginal CAPE values expected across our southeast. ML CIN is in the process of weakening, so initiation s0ouc take place in region of weak convergence. LCLs/LFCs are high with a high melting layer associated with warm/dry adiabatic layer through approximately 700mb. Above this there is limited moisture advection. Drier and more subsident air mass is in our northwest lowering confidence in initiation in all but our NW Kansas counties where strongest precip signal is in place. Due to the dry nature of the soundings coverage should remain isolated to widely scattered. Main axis of forcing transitions east this evening, and loss of daytime heating/stabilization of the boundary layer should lead to any lingering activity diminishing after sunset. Due to the high bases, deep melting layer, and marginal CAPE values in our CWA, confidence in severe hail is lower. On the other hand DCAPE values in the 1500 J/KG range, and Inverted V soundings raises concern for microburst potential. Friday: H5 ridge will be centered roughly across our western CWA, with large scale subsidence and an even drier air mass limiting any thunderstorm potential. Bigger story will be the hot air mass in place, with mean H85 temps at 30-31C range. Warmer guidance is even higher. Warmest layer is actually in the 925mb layer with some guidance showing temps around 37C (98F). With even minor bias corrections the mean/consensus guidance shows highs in the upper 90s, and it is certainly possible for some locations to reach the low 100s. .LONG TERM...(Friday night through Thursday) Issued at 247 PM MDT Thu Jun 9 2016 Friday through Saturday remain hot and dry with the upper ridge moving into place over the central United States and southerly flow at the surface. On Sunday, the upper ridge axis pushes east with a short wave trough aloft lifting out across the central high plains ahead of the main upper trough that starts progressing eastward into the southwestern U.S. A surface trough also associated with the upper wave moves east across the forecast area with a weak cold front to follow overnight Sunday night. Temperatures on Monday will cool somewhat, but will remain slightly above normal with highs in the middle to upper 80s. The best chance of precipitation will be Monday evening through Tuesday as the low over the southwest U.S. lifts out across the Rockies and Central High Plains as an open wave with another surface trough/front expected to move across the forecast area. Temperatures on Tuesday will be slightly cooler on Tuesday as a result. Wednesday and into Thursday look dry and hot again as short wave ridging replaces the trough aloft with high pressure also generally in place across the central U.S. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1135 PM MDT Thu Jun 9 2016 VFR conditions anticipated over the next 24 hours. This is due to abundant dry air that will maintain it`s firm grip on the Tri- State Region. Decided to put LLWS back into the TAF at KMCK. Latest VAD Wind Profile data from KGLD radar indicates a 45 kt low level jet. This is on the fringe of the main jet so think guidance under forecast the strength of the jet. Anticipate LLWS to persist until just before sunrise when the jet weakens and slides east. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...LOCKHART AVIATION...RRH
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1159 PM CDT THU JUN 9 2016 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Friday) Issued at 255 PM CDT THU JUN 9 2016 Weak upper flow continues over the Central Plains this afternoon. A weak upper trough was evident in the water vapor imagery over western Nebraska into to the Texas Panhandle. Another weakening circulation was moving across southeast Kansas and northeast Oklahoma. Surface dry line was located over the high plains and will move very little. Short term models differ with convection this evening with the HRRR and and the RUC moving in some weakening convection from the west during the late evening hours into north central Kansas. The experimental HRRR keeps precipitation to the west and diminishes it before moving to the east of U.S. 81 Highway tonight. Will continue with small precipitation chances in north central Kansas tonight. Lows tonight will continue to be mild with readings in the upper 60s to lower 70s. Friday, Another good warm up is expected with the thermal ridge extending into central Kansas have increased highs slightly into the mid 90s with lower 90s elsewhere across northeast and east central Kansas. The afternoon heat index will reach near 100 degrees across parts of north central and northeast Kansas with the rest of the area in the mid to upper 90s heat index. Weak upper trough/wave moves across central and east Kansas on Friday. There is little in the way of surface moisture convergence with the absence of any boundary and a small EML remains in place through much of the day. The upper trough fills as it moves east with the NAM the strongest with the upper energy. Cannot rule out an isolated late afternoon storm out in central Kansas, but confidence is not high enough to include in forecast at this time. .LONG TERM...(Friday Night through Thursday) Issued at 255 PM CDT THU JUN 9 2016 For Friday night through Sunday, the main question with the forecast is whether a lobe of vorticity gets trapped within the upper ridge over the state. This idea was not in the operational models yesterday, and now have almost a weak closed low aloft near the forecast area during the weekend. Therefore confidence is not all that great. Forecast soundings suggest the airmass will be conditionally unstable with little inhibition to convection. So if this piece of energy is near the area, there could be some diurnally driven convection Saturday and/or Sunday. For now have left POPs around 10 percent but later shifts may need to increase chances if models continue to leave behind this energy within the ridge. The forecast appears to be in good shape regarding forecast temps as there isn`t much chance in the solution`s thermal profiles. Highs are expected to be in the lower and middle 90s as forecast soundings mix the boundary layer to around 825MB. Continued southerly flow and dewpoints holding in the 60s overnight support the lows forecast for temps bottoming out around 70 degrees. Precip chances should be on the increase for Sunday night through much of next week as the upper ridge breaks down and energy from the west passes through the plains. An initial shortwave is progged to pass through the central plains Sunday night and early Monday. Then a more amplified system moves slowly across the plains through Wednesday. The medium range models have come into better agreement in closing off an upper low just north of the forecast area by Wednesday. Think the better chances for precip will be Monday through Tuesday night as the upper wave initially moves out from the southern Rockies and a surface wave lifts across the area. After Wednesday, there are question on where the closed low drifts to and a possible dry slot working into the area. Have held onto some small POPs Wednesday night and across eastern KS for Thursday to account for the closed low in the region. The models show temps trending cooler for next week as the upper system moves through the region. However am a little concerned temps could be to cool as cold raw model guidance seems to be skewing the forecast cooler when there is no significant cold air advection. This is probably due to the models generating precip during these periods. Unless it is cloudy and raining all day, it is hard to see why temps would not continue to be in the lower 90s for Monday and Tuesday. With this in mind have kept highs in the upper 80s and around 90 rather than the middle 80s. There are signs of increasing cold air advection by Wednesday as the upper closed low moves east of the forecast area. With this in mind, have shown a little more of a cool down for the later part of the forecast. && .AVIATION...(For the 06Z TAFS through 06Z Friday Night) Issued at 1158 PM CDT THU JUN 9 2016 For the 06z TAFs, VFR conditions are expected through the period. Some models still suggest that there may be a slight chance for some marginal LLWS overnight, however confidence is not high enough to warrant a mention in the TAFs at this time. Expect the southerly winds to increase once again by late Friday morning, with gusts around 20kts through the afternoon. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...53 LONG TERM...Wolters AVIATION...Hennecke
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
109 AM CDT FRI JUN 10 2016 .UPDATE... Issued at 109 AM CDT Fri Jun 10 2016 We cancelled those portions of severe thunderstorm watch number 240 which are behind the primary, linear band of thunderstorms that extends from near Rugby southward into Sheridan County as of 06 UTC. The line of storms has back-built south of the watch and into eastern Burleigh County east of Bismarck. We will watch radar trends to see if Kidder and Stutsman Counties need to be added to the watch, but at this point trends in intensity suggest we might not need to expand it any further. UPDATE Issued at 1157 PM CDT Thu Jun 9 2016 Another quick update to extend severe thunderstorm watch 240 into Foster County based on upstream radar trends and in collaboration with SPC and WFO Grand Forks. We also trimmed a few more counties in southwest ND from watch 240 with this update. UPDATE Issued at 1127 PM CDT Thu Jun 9 2016 We collaborated with SPC to expand the severe thunderstorm watch downstream of the intense thunderstorms that were centered around Minot at 04 UTC. The severe threat is beginning to diminish to the west, so we also cancelled the watch for Divide, Burke, and Williams Counties. Additional counties in western ND will likely be able to be removed from the watch in the next 90 minutes. UPDATE Issued at 952 PM CDT Thu Jun 9 2016 Overall, the forecast is trending well and only minor changes were made with this update, namely to ramp up PoPs a bit again based on recent HRRR simulations. We discussed the possibility of expanding the severe thunderstorm watch further east into Bismarck/Mandan with SPC, but based on radar trends and some capping shown on the 00 UTC Bismarck sounding the threat appears marginal enough (but certainly non-zero) to hold off on expanding the watch in space at this point. We will continue to re-evaluate that possibility over the next few hours, though. UPDATE Issued at 803 PM CDT Thu Jun 9 2016 Quick update to accommodate a recently-issued severe thunderstorm watch for western and parts of central ND, which is valid through 08 UTC, per collaboration with SPC. We also increased PoPs across much of western and central ND through 09 UTC based on the recent trends in radar imagery, which show increasing storm coverage as forcing attendant to a shortwave trough approaches western ND. UPDATE Issued at 604 PM CDT Thu Jun 9 2016 Only minor changes were made to the forecast with this update. We did spread the chance of thunderstorms eastward a bit more quickly than earlier advertised given radar trends. The severe storms that moved out of northwest and into north central ND are still within an axis of MLCAPE of 2000+ J/kg given surface temperatures in the 90s and dewpoints in the lower 60s F in their inflow region. Very recent radar trends have shown a decreasing trend to those storms, though, which is likely because they are outpacing the stronger deep-layer shear that exists further west. That may marginalize the severe threat with the batch of storms northwest of Minot as of 23 UTC. Meanwhile, convection in southwest ND is high-based in an environment characterized by 40+ F temperature-dewpoint spreads and weak shear as of late afternoon, so we only expect a gusty wind threat with that activity for the next few hours. We are watching storms in MT closely (including one particularly long-lived supercell approaching Jordan as as of 23 UTC). Simple extrapolation of that activity brings it to the ND border by mid evening. If it reaches ND before the boundary layer is able to cool sufficiently for increasing capping to take hold, then there could be a more organized severe threat, particularly over west central and northwest ND. && .SHORT TERM...(This evening through Friday) Issued at 205 PM CDT Thu Jun 9 2016 The expectation of severe thunderstorms west through north central this evening and tonight highlights the short term period. Latest water vapor imagery shows an upper low circulating just off of Vancouver Island with a downstream southwest flow into North Dakota. Shortwaves peeling off from the main low and through the northern Rockies continue to produce thunderstorms in central Montana. The upper level low will meander and head into Washington state Friday before ejecting northeast through southern Canada over the weekend. This slow movement and trajectory keeps western and central ND in a favored area for periodic thunderstorms. The next shortwave to affect western and central ND is seen over western Montana into central Idaho. An associated surface cold front will advance from southern and eastern Montana into North Dakota tonight. Nsharp soundings continue to show high based thunderstorms around 8kft to 10kft west and north central with the primary threat of damaging winds. Dewpoints have been dropping across the west as mixing aloft with drier air ensues. Beach for example went from a 61f dewpoint to 48f dewpoint. Mixed layer cape should be decreasing as a result. Dcape values of around 1500 j/kg across the west late this afternoon and evening indicative of strong downdraft/damaging wind potential. Lcl heights will likely be a bit lower across north central ND as Minot sounding shows dewpoints in the lower 60s holding on through the evening. May see cloud bases around 5kft with an increased depth in cape values. The combination of surface-1km shear of around 25kt, sfc-1km and sfc-3km relative helicity of 189 and 223 meters squared/second squared may provide a brief window of tornado opportunity. The latest HRRR composite reflectivity shows the strongest cells moving across north central between 03z-06z which is coincident with the forecast sounding parameters mentioned above. Thus, damaging winds, large hail, and a possible tornado will be monitored north central early tonight. Convection will taper off from west to east after midnight. .LONG TERM...(Friday night through Thursday) Issued at 205 PM CDT Thu Jun 9 2016 Brief transitory ridging occurs Friday after the passage of Thursday nights shortwave. Thus dry during the daylight hours Friday. Another round of thunderstorms expected Friday night into Saturday, with a second shortwave following for Saturday evening/night. It appears that on Sunday, thunderstorms should be confined from the Turtle Mountains south into the James River Valley. Severe thunderstorms possible with each round, but severe weather is more favored Saturday evening/night along and ahead of a well defined warm front draped over most of western and central North Dakota. SPC maintains a large slight risk area. Continued southwest flow through the middle of next week with signs of another building ridge across central ND which may gradually decrease chances for precipitation later in the week. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 109 AM CDT Fri Jun 10 2016 Thunderstorms with local MVFR and IFR conditions, heavy rain, and gusty winds will move out of central ND by about 11 UTC. VFR conditions will prevail across western and central ND on Friday behind the weak cool front which is generating tonight`s thunderstorm activity. && .BIS Watches/Warnings/Advisories... NONE. && $$ UPDATE...CJS SHORT TERM...KS LONG TERM...KS AVIATION...CJS
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
1157 PM CDT THU JUN 9 2016 .UPDATE... Issued at 1157 PM CDT Thu Jun 9 2016 Another quick update to extend severe thunderstorm watch 240 into Foster County based on upstream radar trends and in collaboration with SPC and WFO Grand Forks. We also trimmed a few more counties in southwest ND from watch 240 with this update. UPDATE Issued at 1127 PM CDT Thu Jun 9 2016 We collaborated with SPC to expand the severe thunderstorm watch downstream of the intense thunderstorms that were centered around Minot at 04 UTC. The severe threat is beginning to diminish to the west, so we also cancelled the watch for Divide, Burke, and Williams Counties. Additional counties in western ND will likely be able to be removed from the watch in the next 90 minutes. UPDATE Issued at 952 PM CDT Thu Jun 9 2016 Overall, the forecast is trending well and only minor changes were made with this update, namely to ramp up PoPs a bit again based on recent HRRR simulations. We discussed the possibility of expanding the severe thunderstorm watch further east into Bismarck/Mandan with SPC, but based on radar trends and some capping shown on the 00 UTC Bismarck sounding the threat appears marginal enough (but certainly non-zero) to hold off on expanding the watch in space at this point. We will continue to re-evaluate that possibility over the next few hours, though. UPDATE Issued at 803 PM CDT Thu Jun 9 2016 Quick update to accommodate a recently-issued severe thunderstorm watch for western and parts of central ND, which is valid through 08 UTC, per collaboration with SPC. We also increased PoPs across much of western and central ND through 09 UTC based on the recent trends in radar imagery, which show increasing storm coverage as forcing attendant to a shortwave trough approaches western ND. UPDATE Issued at 604 PM CDT Thu Jun 9 2016 Only minor changes were made to the forecast with this update. We did spread the chance of thunderstorms eastward a bit more quickly than earlier advertised given radar trends. The severe storms that moved out of northwest and into north central ND are still within an axis of MLCAPE of 2000+ J/kg given surface temperatures in the 90s and dewpoints in the lower 60s F in their inflow region. Very recent radar trends have shown a decreasing trend to those storms, though, which is likely because they are outpacing the stronger deep-layer shear that exists further west. That may marginalize the severe threat with the batch of storms northwest of Minot as of 23 UTC. Meanwhile, convection in southwest ND is high-based in an environment characterized by 40+ F temperature-dewpoint spreads and weak shear as of late afternoon, so we only expect a gusty wind threat with that activity for the next few hours. We are watching storms in MT closely (including one particularly long-lived supercell approaching Jordan as as of 23 UTC). Simple extrapolation of that activity brings it to the ND border by mid evening. If it reaches ND before the boundary layer is able to cool sufficiently for increasing capping to take hold, then there could be a more organized severe threat, particularly over west central and northwest ND. && .SHORT TERM...(This evening through Friday) Issued at 205 PM CDT Thu Jun 9 2016 The expectation of severe thunderstorms west through north central this evening and tonight highlights the short term period. Latest water vapor imagery shows an upper low circulating just off of Vancouver Island with a downstream southwest flow into North Dakota. Shortwaves peeling off from the main low and through the northern Rockies continue to produce thunderstorms in central Montana. The upper level low will meander and head into Washington state Friday before ejecting northeast through southern Canada over the weekend. This slow movement and trajectory keeps western and central ND in a favored area for periodic thunderstorms. The next shortwave to affect western and central ND is seen over western Montana into central Idaho. An associated surface cold front will advance from southern and eastern Montana into North Dakota tonight. Nsharp soundings continue to show high based thunderstorms around 8kft to 10kft west and north central with the primary threat of damaging winds. Dewpoints have been dropping across the west as mixing aloft with drier air ensues. Beach for example went from a 61f dewpoint to 48f dewpoint. Mixed layer cape should be decreasing as a result. Dcape values of around 1500 j/kg across the west late this afternoon and evening indicative of strong downdraft/damaging wind potential. Lcl heights will likely be a bit lower across north central ND as Minot sounding shows dewpoints in the lower 60s holding on through the evening. May see cloud bases around 5kft with an increased depth in cape values. The combination of surface-1km shear of around 25kt, sfc-1km and sfc-3km relative helicity of 189 and 223 meters squared/second squared may provide a brief window of tornado opportunity. The latest HRRR composite reflectivity shows the strongest cells moving across north central between 03z-06z which is coincident with the forecast sounding parameters mentioned above. Thus, damaging winds, large hail, and a possible tornado will be monitored north central early tonight. Convection will taper off from west to east after midnight. .LONG TERM...(Friday night through Thursday) Issued at 205 PM CDT Thu Jun 9 2016 Brief transitory ridging occurs Friday after the passage of Thursday nights shortwave. Thus dry during the daylight hours Friday. Another round of thunderstorms expected Friday night into Saturday, with a second shortwave following for Saturday evening/night. It appears that on Sunday, thunderstorms should be confined from the Turtle Mountains south into the James River Valley. Severe thunderstorms possible with each round, but severe weather is more favored Saturday evening/night along and ahead of a well defined warm front draped over most of western and central North Dakota. SPC maintains a large slight risk area. Continued southwest flow through the middle of next week with signs of another building ridge across central ND which may gradually decrease chances for precipitation later in the week. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1157 PM CDT Thu Jun 9 2016 Thunderstorms with local MVFR and IFR conditions, heavy rain, and gusty winds will move out of western ND by about 08 UTC, and out of central ND by about 11 UTC. VFR conditions will prevail across western and central ND on Friday behind the weak cool front which is generating tonight`s thunderstorm activity. && .BIS Watches/Warnings/Advisories... NONE. && $$ UPDATE...CJS SHORT TERM...KS LONG TERM...KS AVIATION...CJS
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
1127 PM CDT THU JUN 9 2016 .UPDATE... Issued at 1127 PM CDT Thu Jun 9 2016 We collaborated with SPC to expand the severe thunderstorm watch downstream of the intense thunderstorms that were centered around Minot at 04 UTC. The severe threat is beginning to diminish to the west, so we also cancelled the watch for Divide, Burke, and Williams Counties. Additional counties in western ND will likely be able to be removed from the watch in the next 90 minutes. UPDATE Issued at 952 PM CDT Thu Jun 9 2016 Overall, the forecast is trending well and only minor changes were made with this update, namely to ramp up PoPs a bit again based on recent HRRR simulations. We discussed the possibility of expanding the severe thunderstorm watch further east into Bismarck/Mandan with SPC, but based on radar trends and some capping shown on the 00 UTC Bismarck sounding the threat appears marginal enough (but certainly non-zero) to hold off on expanding the watch in space at this point. We will continue to re-evaluate that possibility over the next few hours, though. UPDATE Issued at 803 PM CDT Thu Jun 9 2016 Quick update to accommodate a recently-issued severe thunderstorm watch for western and parts of central ND, which is valid through 08 UTC, per collaboration with SPC. We also increased PoPs across much of western and central ND through 09 UTC based on the recent trends in radar imagery, which show increasing storm coverage as forcing attendant to a shortwave trough approaches western ND. UPDATE Issued at 604 PM CDT Thu Jun 9 2016 Only minor changes were made to the forecast with this update. We did spread the chance of thunderstorms eastward a bit more quickly than earlier advertised given radar trends. The severe storms that moved out of northwest and into north central ND are still within an axis of MLCAPE of 2000+ J/kg given surface temperatures in the 90s and dewpoints in the lower 60s F in their inflow region. Very recent radar trends have shown a decreasing trend to those storms, though, which is likely because they are outpacing the stronger deep-layer shear that exists further west. That may marginalize the severe threat with the batch of storms northwest of Minot as of 23 UTC. Meanwhile, convection in southwest ND is high-based in an environment characterized by 40+ F temperature-dewpoint spreads and weak shear as of late afternoon, so we only expect a gusty wind threat with that activity for the next few hours. We are watching storms in MT closely (including one particularly long-lived supercell approaching Jordan as as of 23 UTC). Simple extrapolation of that activity brings it to the ND border by mid evening. If it reaches ND before the boundary layer is able to cool sufficiently for increasing capping to take hold, then there could be a more organized severe threat, particularly over west central and northwest ND. && .SHORT TERM...(This evening through Friday) Issued at 205 PM CDT Thu Jun 9 2016 The expectation of severe thunderstorms west through north central this evening and tonight highlights the short term period. Latest water vapor imagery shows an upper low circulating just off of Vancouver Island with a downstream southwest flow into North Dakota. Shortwaves peeling off from the main low and through the northern Rockies continue to produce thunderstorms in central Montana. The upper level low will meander and head into Washington state Friday before ejecting northeast through southern Canada over the weekend. This slow movement and trajectory keeps western and central ND in a favored area for periodic thunderstorms. The next shortwave to affect western and central ND is seen over western Montana into central Idaho. An associated surface cold front will advance from southern and eastern Montana into North Dakota tonight. Nsharp soundings continue to show high based thunderstorms around 8kft to 10kft west and north central with the primary threat of damaging winds. Dewpoints have been dropping across the west as mixing aloft with drier air ensues. Beach for example went from a 61f dewpoint to 48f dewpoint. Mixed layer cape should be decreasing as a result. Dcape values of around 1500 j/kg across the west late this afternoon and evening indicative of strong downdraft/damaging wind potential. Lcl heights will likely be a bit lower across north central ND as Minot sounding shows dewpoints in the lower 60s holding on through the evening. May see cloud bases around 5kft with an increased depth in cape values. The combination of surface-1km shear of around 25kt, sfc-1km and sfc-3km relative helicity of 189 and 223 meters squared/second squared may provide a brief window of tornado opportunity. The latest HRRR composite reflectivity shows the strongest cells moving across north central between 03z-06z which is coincident with the forecast sounding parameters mentioned above. Thus, damaging winds, large hail, and a possible tornado will be monitored north central early tonight. Convection will taper off from west to east after midnight. .LONG TERM...(Friday night through Thursday) Issued at 205 PM CDT Thu Jun 9 2016 Brief transitory ridging occurs Friday after the passage of Thursday nights shortwave. Thus dry during the daylight hours Friday. Another round of thunderstorms expected Friday night into Saturday, with a second shortwave following for Saturday evening/night. It appears that on Sunday, thunderstorms should be confined from the Turtle Mountains south into the James River Valley. Severe thunderstorms possible with each round, but severe weather is more favored Saturday evening/night along and ahead of a well defined warm front draped over most of western and central North Dakota. SPC maintains a large slight risk area. Continued southwest flow through the middle of next week with signs of another building ridge across central ND which may gradually decrease chances for precipitation later in the week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 952 PM CDT Thu Jun 9 2016 Showers and thunderstorms will move across western and central ND through about 10 UTC. Local MVFR and IFR conditions and gusty winds are expected with thunderstorms, and some could be severe with large hail and damaging winds, especially in western and north central ND. && .BIS Watches/Warnings/Advisories... NONE. && $$ UPDATE...CJS SHORT TERM...KS LONG TERM...KS AVIATION...CJS Area Forecast Discussion National Weather Service Flagstaff AZ 251 AM MST SUN JUN 12 2016 .SYNOPSIS...Dry and breezy conditions are forecast today, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. Record high temperatures look to make a return by next weekend. && .DISCUSSION...Breezy conditions are expected across northern Arizona this afternoon as an upper-level trough, currently just off the southern California coast, slowly makes its way eastward. Ample dry air throughout the lower and upper levels of the atmosphere should prevent any precipitation from developing today. Monday...As the trough swings through the region, there will be enough moisture/instability for a few showers and storms to develop during the late morning and afternoon hours, mainly north of I-40. The best chances will be along and north of a line from the Grand Canyon to Window Rock. Tuesday through Friday...Dry weather is expected through this period along with a warming trend as high pressure begins to build into the area. High temperatures will rise to 5 to 10 degrees above normal by Friday. Additionally, breezy southwest winds may make for near critical to critical fire weather conditions on Wednesday and Thursday. Saturday and Sunday...All the major global models are in agreement with a very strong ridge of high pressure settling over Arizona. This is still a week out, so the exact strength and placement of the high is subject to change. However, early signs point to record high temperatures returning to Arizona. This ridge is forecast to be even stronger than the last one that brought record temperatures to the state. The NAEFS and GEFS mean have this ridge in the 99th to 100th percentile, meaning the models are expecting this ridge to be abnormally strong, even for June. The current forecast is calling for temperatures to generally be 10 to 15 degrees above normal. && .AVIATION...For the 12Z Package...A drier air mass will bring mainly VFR conditions over the next 24 hours. There will be a slight chance of showers and thunderstorms across the area of the Arizona/New Mexico border. Afternoon Southwest winds 10-20 kts gusting to 30 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A drier air mass will move over Arizona today with just a slight chance of showers and thunderstorms near the Arizona/New Mexico border. On Monday, a few isolated showers possible along and north of Interstate 40 with the passage of a weather disturbance. Southwest winds in the 10 to 20 mph range each afternoon. Tuesday through Thursday...Dry southwesterly flow will dominate the weather across Arizona with afternoon humidity values potentially dropping into the single digits and gusty winds each day. Critical fire weather conditions will be possible. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Mottice AVIATION...McCollum FIRE WEATHER...McCollum For Northern Arizona weather information visit weather.gov/flagstaff
  [top] Area Forecast Discussion National Weather Service Tucson AZ 235 AM MST SUN JUN 12 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border this afternoon followed by dry condiitons Monday through next weekend. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through next weekend. && .DISCUSSION...The pre-Monsoon thunderstorm action of the past two days is coming to an end. A few storms are still possible near the New Mexico border today otherwise drier air continues to push in from the west over the area. Cooler than normal temperatures today into Tuesday then a warming trend during the second half of the work week with the furnace being turned on next weekend. Models consistent on developing a very strong high pressure ridge over the area next weekend with 500 mb heights approaching 600 DM. Based on in house low level thickness value study highs next weekend have the potential to be hotter than what occurred earlier this month and will approach record highs on the 17th thru the 19th. Could end up being historic as some places may end up close to not only all-time June record highs but all-time yearly record highs. A little early for issuance of an excessive heat watch but will be getting the message out via social media platforms today. && .AVIATION...VALID THRU 13/12Z. Scattered clouds from 10-12k ft msl near the New Mexico border this afternoon with slgt chc of -shra/-tsra, otherwise SKC. Surface winds less than 10 kts...then becoming W/SW this afternoon at 10-18 kts with gusts to 25 kts. Wind diminishing after sunset to less than 10 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...A slight chance of thunderstorms near the New Mexico border this afternoon. Dry conditions will then prevail Monday through next weekend. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
  [top] Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Tucson AZ 909 PM MST SAT JUN 11 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border Sunday followed by dry condiitons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Showers and thunderstorms that developed this afternoon across parts of southeast Arizona have ended late this evening. Still looking at some debris cloudiness east of Tucson, with clear skies elsewhere. General clearing will continue overnight tonight, with a few cloud build ups and isolated thunderstorms near the New Mexico border tomorrow afternoon. Current forecast handled these trends well, so no updates expected this evening. && .AVIATION...VALID THRU 13/06Z. Cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .PREV DISCUSSION...11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 853 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated showers will continue over northern Coconino county through Saturday evening. Otherwise...dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Convection is rapidly decreasing this evening...with isolated showers expected til midnight over N. Coconin county. Grids are in great shape, and no updates are planned at this time. && .PREV DISCUSSION.../323pm mst/...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 06Z Package...VFR conditions expected through Sunday...with southerly winds gusting to 30kts Sunday afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM/BAK AVIATION/FIRE WEATHER...Bohlin/BAK For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 330 PM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Scattered showers and thunderstorms were ongoing mostly north-to-east of the Tucson metro area this afternoon. Various 11/12Z NWP models suggest the bulk of these showers and thunderstorms will gradually decrease in coverage and intensity during the next several hours. Expect isolated to scattered showers and thunderstorms mainly from Tucson east to the New Mexico border this evening. A slight chance of showers and thunderstorms then continues late tonight into Sunday evening mainly near the New Mexico border. 11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity nwd/ewd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight thru Sunday afternoon. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson northward, and eastward to the New Mexico border. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 323 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION/FIRE WEATHER...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 308 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend (June 19). && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Phoenix AZ 224 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next several days resulting in somewhat cooler weather through early next week. Showers and thunderstorms will also be pushed well east as drier air moves back into the region. After several relatively comfortable days with near normal temperatures through the middle of next week, excessively hot weather will likely settle back into the area by the end of next week. && .DISCUSSION... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Isolated showers and thunderstorms should only impact areas south of the Phoenix metro through the rest of the afternoon, but confidence is not high enough to totally rule a shower or storm to briefly affect southern portions of the metro area. Breezy southerly winds will eventually turn westerly this evening for the Phoenix terminals and remain westerly through much of the overnight. After midnight the area will be under drying conditions and clearing skies. Gusty southerly winds will affect southeast California including KBLH and KIPL through around midnight with winds 10 kts or less thereafter. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Nolte/MO AVIATION...Kuhlman FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Flagstaff AZ 1218 PM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Convection is firing over the higher terrain of Yavapai county and western Coconino county early this afternoon. Thunderstorm activity is also developing over southern Apache county in the vicinity of the White Mountains. Think the convection over Yavapai/western Coconino counties will expand in coverage this afternoon due to increasing instability. Updated the forecast to expand scattered coverage of afternoon thunderstorms into the North Rim area based on current obs/trends. The remaining weather elements are in good shape. The updated forecast has been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with scattered coverage over Yavapai and western Coconino counties. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 935 AM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Current visible satellite imagery shows convective clouds beginning to develop over Yavapai and western Coconino counties. Furthermore, a mid/high level cloud deck over most of Navajo and all of Apache counties should continue to lift north of the region through the afternoon. The latest high-res models prog increasing instability over Yavapai and western Coconino counties today. Furthermore, with dewpoints in the upper 40s and 50s, think enough lift and instability should initiate convection along the Mogollon Rim this afternoon. Weak deep layer shear should keep convection below severe limits. Updated the forecast based on current obs/trends. Increased the temporal resolution of pops in order to try and best time the convection across northern Arizona this afternoon. Otherwise, the remaining forecast is on track. The updated products have been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with isolated coverage in northwestern Arizona and more scattered coverage in northeastern Arizona. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. High pressure builds in from Tuesday onward with hot and dry weather. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 915 AM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...11/12Z Univ of AZ WRF-NAM and several HRRR solutions suggest that showers/tstms will develop near the Tucson metro area eastward/southward later this morning into early this afternoon. These cells will then move quickly nwd/newd, with the main concern for potentially damaging wind gusts. The bulk of these showers/ tstms will end this evening. There are no updates planned at this time. Please refer to the additional sections for further detail. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity ewd/swd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight into Sunday morning. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson east and south. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through Friday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next Friday. && .PREV DISCUSSION /234 AM MST/...Precipitable water values remain well above mid-June normals this morning with values mostly in the 1.00"-1.50" range. Water vapor imagery showed an upper level low approaching southern CA. Drier air will start to push in from the west as the day progresses, but enough will be around across the eastern 2/3rds of the area for isolated valley/scattered mountains showers and thunderstorms. Precipitable water values are forecast to be below 1" on Sunday with a slight chance of storms relegated to the White mountains. High temperatures this weekend will remain several degrees below normal. Upper level trof will push across the state on Monday providing slightly cooler daytime temperatures and further drying of the atmosphere. Upper ridge strengthens over the area Tuesday through Friday resulting in warmer daytime high temperatures. Outside of this forecast package are likely hotter daytime temperatures as the upper ridge continues to strengthen over the area. Highs next weekend could rival what occurred earlier this month. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
119 AM EDT SUN JUN 12 2016 .SYNOPSIS... Issued at 945 PM EDT Sat Jun 11 2016 A cold front will move through the area tonight...bringing cooler and less humid air for Sunday. Shower and thunderstorm chances will return for much of the upcoming work week as the front returns north and remains over the region. Lows tonight will range from the lower 60s north to near 70 south. Highs on Sunday will be in the upper 70s to middle 80s...with locally cooler conditions near Lake Michigan. && .UPDATE... Issued at 945 PM EDT Sat Jun 11 2016 Loss of daytime heating and limited forcing has allowed all shower development to cease across the area with the remainder of the evening expected to be dry. Well defined cold front noted from Saginaw Bay west to north of Muskegon with a noticeable drop in temps and dewpoints (at least 10 degree drop on both elements) behind the front. Forcing along the front has broke through the cap immediately ahead of the front with a few showers from Mt Pleasant MI ENE into Saginaw Bay. Much more capped atmosphere should be in place further south to keep this activity from surviving too long. Hi res models have generally backed off on any development with the front...but given at least limited instability still in place across the area and slightly increased shear with the front...can`t rule out a stray shower or storm. Still not quite worthy of a mention in the grids/zones with the evening update. && .SHORT TERM...(This Evening through Sunday) Issued at 317 PM EDT Sat Jun 11 2016 Outflow from overnight MCS to our north effectively squashed convection this afternoon as we thought was a possibility. RUC point soundings show high CAPE but little effective shear and rather large temp/dew point depressions for convective initiation. Weak pre- frontal trough and convectively enhanced short wave moved through northeast area earlier today helping bring sfc winds around to west northwest...further limiting low level convergence. On the plus side, radar and satellite showing a couple boundaries that were trying to convect at issuance. Northern boundary appears to be lake enhanced and lies across northern Indiana. Second boundary located over south central forecast area and is drifting east. A couple cells have developed along these boundaries and currently dropping quick heavy rainfall with some signs of lightning and outflows. Given very unstable conditions these pulse storms expected through early evening with heavy rain. Large CAPE and evaporative cooling could yield brief and isolated strong to severe wind gusts. Main synoptic cold front slides south through the area overnight. Could be a few isolated showers near boundary per a few hires models but at this point plan on leaving out of forecast. Drier air will filter in late tonight. Surface high to slide southeast from upper Midwest across the western Lakes Sunday while mid level ridge builds to our west. This will provide a comfortable day with north to northeast winds. && .LONG TERM...(Sunday Night through Saturday) Issued at 317 PM EDT Sat Jun 11 2016 High pressure will be over the area at start of period but will be sliding east as return flow develops. Another upper midwest MCS looks likely Sunday night as short wave tops plains ridge. Convectively enhanced short wave then looks to drop southeast Monday and helps bring a weak front into the north late as heights fall. This will set the stage for shower and thunderstorm chances through much of the week as this boundary becomes quasi stationary and meanders across the region with short wave energy emanating east from a developing mid level closed low to our west. This low will then drift towards the area by mid to late week with additional showers and thunderstorms in its vicinity. Models have shown various solutions with track and timing of this low. Prefer slower solutions but its exact southeastward track remains uncertain. Really no choice but to continue chance pops through much of the upcoming week though it will be dry for a large part of the time with occasional convective chances. Details to be refined as the week progresses. Temperatures to remain seasonably warm in the 80s with clouds and pcpn chances impacting these numbers day to day. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 118 AM EDT Sun Jun 12 2016 vfr conds xpcd this pd as ridging sfc and aloft rebuilds acrs the region. && .IWX Watches/Warnings/Advisories... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...Fisher SYNOPSIS...Fisher SHORT TERM...Lashley LONG TERM...Lashley AVIATION...T Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1147 PM CDT SAT JUN 11 2016 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Sunday) Issued at 325 PM CDT SAT JUN 11 2016 A weak MCV was moving across northwest Missouri this afternoon which formed from an earlier MCS over Iowa this morning. Short term high resolution models have been showing convection developing through the morning and afternoon in northeast and east central Kansas. Latest RUC soundings show a weak cap remaining in place through peak heating. Cumulus remains rather flat across the area this afternoon similar to previous afternoons. Upper level ridge remains in place across the Central Plains. Tonight expect the cumulus clouds to dissipate with the loss of heating with mostly clear skies expected. Lows tonight will be similar to last night with low to mid 70s common. Sunday models continue to show some mid level energy over northeast Oklahoma and southeast Kansas. There may be enough lift in the afternoon when atmosphere becomes uncapped for isolated thunderstorms to develop from southeast Kansas into Arkansas and will leave east central Kansas dry for now with model qpf clustering to the southeast of the cwa. Highs on Sunday will be similar to today with highs in the low to mid 90s. Heat indices will again approach 100 degrees across parts of the area on Sunday afternoon. .LONG TERM...(Sunday Night through Saturday) Issued at 325 PM CDT SAT JUN 11 2016 Sunday night through Tuesday, storm chances increase for much of the period. Late Sunday evening have gone with slight chance POPs over southern to western portions of the area as perhaps weak forcing may provide enough lift in a moist environment to cause a few showers and thunderstorms. The chance remains small at this point as the boundary layer will remain mostly capped off and a weak upper circulation advances into southern Missouri. Late Sunday, a storm complex develops over west central Nebraska along the nose of a LLJ and slowly works its way southeast into the forecast area by early morning into a less favorably sheared environment and an area of smaller scale shortwave ridging. During the day, remnant thunderstorm activity and an uncapped environment should lead to mostly cloudy conditions with a few thunderstorms possible over eastern portions of the forecast area where weak ridging will still be influencing the area but continuing to be suppressed as larger scale forcing advances from the west. Therefore, have left chance POPs over western portions of the forecast area into the afternoon on Monday. Tuesday night, a LLJ will likely aid in the development of thunderstorms over western KS and as storms grow upscale, another complex may develop and begin to advance into the north central Kansas and on into northeastern Kansas over night. Most long term guidance is generally in better agreement but still details seem to be in question such as exact positioning of the upper wave and strength of the upper wave as it moves out of the Central Rockies into the Central Plains. Previous runs have shown this wave to actually be a closed off low and more intense but that has been backed off at this point a bit and now the overall flow of the southern stream energy may be a bit weaker. Regardless, a more northerly track of the upper low seems to make sense based on current positioning just off the SoCal region. Depending on the actual strength of the upper trough feature, it seems to make sense that as the overnight MCS organizes out west and moves into western portions of the forecast area it could be sustained through the morning into the early afternoon hours as shear profiles increase to above 35kts, MUCAPE reaches to around 2,000 to 2,500 J/kg and mid- level lapse rates increase to at least conditional and probably up to around 7 C/km. Of course, some changes will likely occur between now and Tuesday as to how much severe potential we end up with, but at least some needed rain will likely fall over much of the area as the long term forecast looks mainly dry after this round of precip with possibly the exception of next Friday time frame as a frontogenetical response sets up on the backside of the wave previously mentioned as it transitions into a cut-off low eventually working back into portions of the Ohio and mid MS Valley regions before filling and transitioning into a frontal system over the East coast region. Temps cool back a bit into the mid and upper 80s by next weekend as more zonal flow sets up over the Northern into Central Plains. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1142 PM CDT SAT JUN 11 2016 Sfc high pressure to the southeast keeps winds below 10 kts through the period. Overall VFR conditions with a brief period of BR or haze near sunrise. Thunder chances are low from 00Z onward so did not include. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...53 LONG TERM...Drake AVIATION...Prieto Area Forecast Discussion National Weather Service Phoenix AZ 848 AM MST SUN JUN 12 2016 .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Considerable drying has occurred over the past 24 hours with PWATS falling to well below an inch. Given the drop in moisture levels there is now little to no chance of any additional shower or thunderstorm activity. Skies will remain clear aside from a few mid level afternoon CU mainly focused over the south-central Arizona higher terrain. A slow moving upper level trough currently off the Southwest U.S. coast will move into the region tonight into Monday, but no additional moisture will be added, so the only result will be the continued slightly below normal temperatures. I made some minor adjustments to sky cover to add in more areal CU coverage for this afternoon. The rest of the forecast is on track with no other adjustments are needed. && .PREVIOUS DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather impacts through Monday morning with only Few-Sct CU developing over the mountains this afternoon. Winds around central Arizona may obtain a cross runway southerly component near 10kt for a few hours late this morning before veering to the more traditional W/SW direction. A few gusts 20-25kt will be possible, but confidence in prolonged stronger gusts is low. Across SE CA, winds will favor a S/SW type direction though may be light and variable on occasion. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate the region through the weekend as high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Tuesday and Wednesday increasing to at least 10F above average (and near record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Kuhlman PREVIOUS DISCUSSION...Hernandez CLIMATE...MO AVIATION...MO FIRE WEATHER...MO/Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 440 AM MST SUN JUN 12 2016 ...Updated Aviation and Fire Weather... .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather impacts through Monday morning with only Few-Sct CU developing over the mountains this afternoon. Winds around central Arizona may obtain a cross runway southerly component near 10kt for a few hours late this morning before veering to the more traditional W/SW direction. A few gusts 20-25kt will be possible, but confidence in prolonged stronger gusts is low. Across SE CA, winds will favor a S/SW type direction though may be light and variable on occasion. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate the region through the weekend as high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Tuesday and Wednesday increasing to at least 10F above average (and near record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hernandez CLIMATE...MO AVIATION...MO FIRE WEATHER...MO/Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 309 AM MST SUN JUN 12 2016 .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hernandez AVIATION...AJ FIRE WEATHER...Kuhlman
  [top] Area Forecast Discussion National Weather Service Flagstaff AZ 251 AM MST SUN JUN 12 2016 .SYNOPSIS...Dry and breezy conditions are forecast today, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. Record high temperatures look to make a return by next weekend. && .DISCUSSION...Breezy conditions are expected across northern Arizona this afternoon as an upper-level trough, currently just off the southern California coast, slowly makes its way eastward. Ample dry air throughout the lower and upper levels of the atmosphere should prevent any precipitation from developing today. Monday...As the trough swings through the region, there will be enough moisture/instability for a few showers and storms to develop during the late morning and afternoon hours, mainly north of I-40. The best chances will be along and north of a line from the Grand Canyon to Window Rock. Tuesday through Friday...Dry weather is expected through this period along with a warming trend as high pressure begins to build into the area. High temperatures will rise to 5 to 10 degrees above normal by Friday. Additionally, breezy southwest winds may make for near critical to critical fire weather conditions on Wednesday and Thursday. Saturday and Sunday...All the major global models are in agreement with a very strong ridge of high pressure settling over Arizona. This is still a week out, so the exact strength and placement of the high is subject to change. However, early signs point to record high temperatures returning to Arizona. This ridge is forecast to be even stronger than the last one that brought record temperatures to the state. The NAEFS and GEFS mean have this ridge in the 99th to 100th percentile, meaning the models are expecting this ridge to be abnormally strong, even for June. The current forecast is calling for temperatures to generally be 10 to 15 degrees above normal. && .AVIATION...For the 12Z Package...A drier air mass will bring mainly VFR conditions over the next 24 hours. There will be a slight chance of showers and thunderstorms across the area of the Arizona/New Mexico border. Afternoon Southwest winds 10-20 kts gusting to 30 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A drier air mass will move over Arizona today with just a slight chance of showers and thunderstorms near the Arizona/New Mexico border. On Monday, a few isolated showers possible along and north of Interstate 40 with the passage of a weather disturbance. Southwest winds in the 10 to 20 mph range each afternoon. Tuesday through Thursday...Dry southwesterly flow will dominate the weather across Arizona with afternoon humidity values potentially dropping into the single digits and gusty winds each day. Critical fire weather conditions will be possible. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Mottice AVIATION...McCollum FIRE WEATHER...McCollum For Northern Arizona weather information visit weather.gov/flagstaff
  [top] Area Forecast Discussion National Weather Service Tucson AZ 235 AM MST SUN JUN 12 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border this afternoon followed by dry condiitons Monday through next weekend. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through next weekend. && .DISCUSSION...The pre-Monsoon thunderstorm action of the past two days is coming to an end. A few storms are still possible near the New Mexico border today otherwise drier air continues to push in from the west over the area. Cooler than normal temperatures today into Tuesday then a warming trend during the second half of the work week with the furnace being turned on next weekend. Models consistent on developing a very strong high pressure ridge over the area next weekend with 500 mb heights approaching 600 DM. Based on in house low level thickness value study highs next weekend have the potential to be hotter than what occurred earlier this month and will approach record highs on the 17th thru the 19th. Could end up being historic as some places may end up close to not only all-time June record highs but all-time yearly record highs. A little early for issuance of an excessive heat watch but will be getting the message out via social media platforms today. && .AVIATION...VALID THRU 13/12Z. Scattered clouds from 10-12k ft msl near the New Mexico border this afternoon with slgt chc of -shra/-tsra, otherwise SKC. Surface winds less than 10 kts...then becoming W/SW this afternoon at 10-18 kts with gusts to 25 kts. Wind diminishing after sunset to less than 10 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...A slight chance of thunderstorms near the New Mexico border this afternoon. Dry conditions will then prevail Monday through next weekend. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Tucson AZ 909 PM MST SAT JUN 11 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border Sunday followed by dry condiitons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Showers and thunderstorms that developed this afternoon across parts of southeast Arizona have ended late this evening. Still looking at some debris cloudiness east of Tucson, with clear skies elsewhere. General clearing will continue overnight tonight, with a few cloud build ups and isolated thunderstorms near the New Mexico border tomorrow afternoon. Current forecast handled these trends well, so no updates expected this evening. && .AVIATION...VALID THRU 13/06Z. Cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .PREV DISCUSSION...11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 853 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated showers will continue over northern Coconino county through Saturday evening. Otherwise...dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Convection is rapidly decreasing this evening...with isolated showers expected til midnight over N. Coconin county. Grids are in great shape, and no updates are planned at this time. && .PREV DISCUSSION.../323pm mst/...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 06Z Package...VFR conditions expected through Sunday...with southerly winds gusting to 30kts Sunday afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM/BAK AVIATION/FIRE WEATHER...Bohlin/BAK For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 330 PM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Scattered showers and thunderstorms were ongoing mostly north-to-east of the Tucson metro area this afternoon. Various 11/12Z NWP models suggest the bulk of these showers and thunderstorms will gradually decrease in coverage and intensity during the next several hours. Expect isolated to scattered showers and thunderstorms mainly from Tucson east to the New Mexico border this evening. A slight chance of showers and thunderstorms then continues late tonight into Sunday evening mainly near the New Mexico border. 11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity nwd/ewd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight thru Sunday afternoon. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson northward, and eastward to the New Mexico border. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 323 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION/FIRE WEATHER...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 308 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend (June 19). && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Phoenix AZ 224 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next several days resulting in somewhat cooler weather through early next week. Showers and thunderstorms will also be pushed well east as drier air moves back into the region. After several relatively comfortable days with near normal temperatures through the middle of next week, excessively hot weather will likely settle back into the area by the end of next week. && .DISCUSSION... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Isolated showers and thunderstorms should only impact areas south of the Phoenix metro through the rest of the afternoon, but confidence is not high enough to totally rule a shower or storm to briefly affect southern portions of the metro area. Breezy southerly winds will eventually turn westerly this evening for the Phoenix terminals and remain westerly through much of the overnight. After midnight the area will be under drying conditions and clearing skies. Gusty southerly winds will affect southeast California including KBLH and KIPL through around midnight with winds 10 kts or less thereafter. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Nolte/MO AVIATION...Kuhlman FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Flagstaff AZ 1218 PM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Convection is firing over the higher terrain of Yavapai county and western Coconino county early this afternoon. Thunderstorm activity is also developing over southern Apache county in the vicinity of the White Mountains. Think the convection over Yavapai/western Coconino counties will expand in coverage this afternoon due to increasing instability. Updated the forecast to expand scattered coverage of afternoon thunderstorms into the North Rim area based on current obs/trends. The remaining weather elements are in good shape. The updated forecast has been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with scattered coverage over Yavapai and western Coconino counties. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 935 AM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Current visible satellite imagery shows convective clouds beginning to develop over Yavapai and western Coconino counties. Furthermore, a mid/high level cloud deck over most of Navajo and all of Apache counties should continue to lift north of the region through the afternoon. The latest high-res models prog increasing instability over Yavapai and western Coconino counties today. Furthermore, with dewpoints in the upper 40s and 50s, think enough lift and instability should initiate convection along the Mogollon Rim this afternoon. Weak deep layer shear should keep convection below severe limits. Updated the forecast based on current obs/trends. Increased the temporal resolution of pops in order to try and best time the convection across northern Arizona this afternoon. Otherwise, the remaining forecast is on track. The updated products have been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with isolated coverage in northwestern Arizona and more scattered coverage in northeastern Arizona. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. High pressure builds in from Tuesday onward with hot and dry weather. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 915 AM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...11/12Z Univ of AZ WRF-NAM and several HRRR solutions suggest that showers/tstms will develop near the Tucson metro area eastward/southward later this morning into early this afternoon. These cells will then move quickly nwd/newd, with the main concern for potentially damaging wind gusts. The bulk of these showers/ tstms will end this evening. There are no updates planned at this time. Please refer to the additional sections for further detail. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity ewd/swd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight into Sunday morning. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson east and south. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through Friday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next Friday. && .PREV DISCUSSION /234 AM MST/...Precipitable water values remain well above mid-June normals this morning with values mostly in the 1.00"-1.50" range. Water vapor imagery showed an upper level low approaching southern CA. Drier air will start to push in from the west as the day progresses, but enough will be around across the eastern 2/3rds of the area for isolated valley/scattered mountains showers and thunderstorms. Precipitable water values are forecast to be below 1" on Sunday with a slight chance of storms relegated to the White mountains. High temperatures this weekend will remain several degrees below normal. Upper level trof will push across the state on Monday providing slightly cooler daytime temperatures and further drying of the atmosphere. Upper ridge strengthens over the area Tuesday through Friday resulting in warmer daytime high temperatures. Outside of this forecast package are likely hotter daytime temperatures as the upper ridge continues to strengthen over the area. Highs next weekend could rival what occurred earlier this month. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson Area Forecast Discussion National Weather Service Flagstaff AZ 355 PM MST SUN JUN 12 2016 .SYNOPSIS...Cool conditions for mid-June are forecast for Monday with a chance of thunderstorms mainly near/north of I-40. A drying/warming trend will commence Tuesday, and will continue through the end of this coming weekend. Record high temperatures look to make a return by this coming weekend. && .DISCUSSION... Visible satellite shows an extensive cumulus field across most of northern Arizona. Radar shows that storm/shower activity is limited to western New Mexico, and has moved somewhat eastward with time as forecast. Other shower activity is located northwest of Las Vegas. Expect a dry remainder of the afternoon/evening across the CWA with breezy southwest winds continuing through sunset. Mainly isolated thunderstorms are forecast near and north of Interstate 40 from the early morning hours Monday through Monday afternoon, with somewhat greater coverage possible on the Kaibab Plateau and Black Mesa/areas near the Utah state line. This is in association with some moisture being brought northward ahead of the trough axis as it swings through northern Arizona late tomorrow afternoon. A cool day for mid-June is expected tomorrow along with breezy afternoon winds, especially in eastern Arizona. A pronounced warming trend starts on Tuesday and continues through the week as a strong ridge begins to build over the southwest U.S. A trough passing well to the northwest of Arizona may still allow for winds to become quite breezy on Wednesday afternoon along with the warm temperatures and very dry air. By this weekend, NAEFS climatological percentiles indicate that we will be at least into the 90-95th percentile range for 700mb temps/500mb heights, even higher in a few locations. This lasts into Monday- Tuesday. Forecast temperatures have led us to issue an Excessive Heat Watch for elevations below 4000 feet in Yavapai/northern Gila Counties and the Grand Canyon. The watch is valid through Monday for now, but may eventually need to be extended in time. We`d best enjoy the cool temperatures tomorrow, because this coming weekend will be a cooker. && .AVIATION...For the 00Z Package...Mainly VFR conds over the next 24 hrs. A low pressure trough is forecast to swing across the region producing Isold-Sct shra/tsra mainly N of a line from KPRC-KFGZ-KRQE starting aft 06z tonight. Afternoon SW winds 10-20 kts G30 kts dcrsg aft sunset tonight then SW winds 10-20 kts G30kts incrsg again aft 16z Monday. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Winds will taper off overnight tonight before becoming breezy again Monday afternoon. Isolated showers and thunderstorms are also possible north of Interstate 40 Monday afternoon and evening as a weak trough passes through the area. The dry weather will continue Tuesday but with weaker winds. Wednesday through Friday...Strong southwesterly winds and RH values in the single digits to low teens will support near-critical fire conditions Wednesday afternoon. Strong high pressure begins building in from the east on Thursday and Friday with well-above average temperatures, very low RH`s, and weaker winds this weekend. && .FGZ WATCHES/WARNINGS/ADVISORIES...Excessive Heat Watch from Saturday morning through Monday evening FOR AZZ006-018-037. && $$ PUBLIC...Taylor AVIATION...TC FIRE WEATHER...TRC For Northern Arizona weather information visit weather.gov/flagstaff
  [top] Area Forecast Discussion National Weather Service Phoenix AZ 205 PM MST SUN JUN 12 2016 .SYNOPSIS... A dry low pressure system will move across the region through Tuesday keeping temperatures near normal. As high pressure starts building to our southeast, a dramatic warming trend will start on Wednesday with near or slightly above normal temperatures through Thursday. A large heat dome under a very strong high pressure system will develop starting Friday and persist into next weekend with record high temperatures for next weekend. && .DISCUSSION... A significant heat episode for next weekend is very likely and will surely break daily records and potentially compete with past heat events where Phoenix hit 120F. Before this heat event develops, near or slightly below normal temperatures will be seen through the middle of this week. Southerly flow ahead of an upper level trough off the Southwest U.S. coast is currently bringing drying conditions to our region as evident via water vapor imagery and a large area of blended total precipitable water values of around 2/3 of an inch. This trough will move through the Desert Southwest through Monday night keeping temperatures rather mild with highs generally in a 95-102 range across the deserts. A high amplitude synoptic regime develops during the middle of this week as a deep upper low becomes entrenched over the Pacific Northwest. This will allow the ridge over the Southern Plains to strengthen and retrograde to the west. Strong model agreement shows 500mb heights building from around 586dm on Wednesday to 592-594dm on Friday and even as high as 600dm heights centered just south of the Four Corners area on Sunday. Highs by Friday will likely top 110 degrees over the south-central Arizona deserts and continue to climb into the weekend under near record heights aloft. As 850mb temperatures climb to near 35C by Sunday, we should be seeing widespread high temperatures of 115-120F. This could end up being a long duration excessive heat event, but beyond next Monday model spread increases. There are also indications of some moisture that may advect in from from the east and heights should gradually lower back toward 590-594dm after next Monday. Either way, there is enough confidence to issue an Excessive Heat Watch starting Friday for the south-central Arizona deserts spreading nearly all other areas for next Saturday through Monday. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major weather aviation impacts to consider. Few-Sct CU developing so far this afternoon over the eastern mountains but should stay well out of the terminal area. Winds otherwise follow their typical W/SW direction around 10-15kts for all TAF sites with some afternoon gustiness around 20-25kts possible. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Wednesday through Sunday... Dry air will dominate the region through the weekend as strong high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Wednesday increasing to at least 10F above average (record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Excessive Heat Watch from Friday morning through Monday evening for AZZ022-023-027-028. Excessive Heat Watch from Saturday morning through Monday evening for AZZ020-021-024>026. CA...Excessive Heat Watch from Saturday morning through Monday evening for CAZ031>033. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Kuhlman CLIMATE...MO AVIATION...MO FIRE WEATHER...Deemer
Area Forecast Discussion National Weather Service Phoenix AZ 205 PM MST SUN JUN 12 2016 .SYNOPSIS... A dry low pressure system will move across the region through Tuesday keeping temperatures near normal. As high pressure starts building to our southeast, a dramatic warming trend will start on Wednesday with near or slightly above normal temperatures through Thursday. A large heat dome under a very strong high pressure system will develop starting Friday and persist into next weekend with record high temperatures for next weekend. && .DISCUSSION... A significant heat episode for next weekend is very likely and will surely break daily records and potentially compete with past heat events where Phoenix hit 120F. Before this heat event develops, near or slightly below normal temperatures will be seen through the middle of this week. Southerly flow ahead of an upper level trough off the Southwest U.S. coast is currently bringing drying conditions to our region as evident via water vapor imagery and a large area of blended total precipitable water values of around 2/3 of an inch. This trough will move through the Desert Southwest through Monday night keeping temperatures rather mild with highs generally in a 95-102 range across the deserts. A high amplitude synoptic regime develops during the middle of this week as a deep upper low becomes entrenched over the Pacific Northwest. This will allow the ridge over the Southern Plains to strengthen and retrograde to the west. Strong model agreement shows 500mb heights building from around 586dm on Wednesday to 592-594dm on Friday and even as high as 600dm heights centered just south of the Four Corners area on Sunday. Highs by Friday will likely top 110 degrees over the south-central Arizona deserts and continue to climb into the weekend under near record heights aloft. As 850mb temperatures climb to near 35C by Sunday, we should be seeing widespread high temperatures of 115-120F. This could end up being a long duration excessive heat event, but beyond next Monday model spread increases. There are also indications of some moisture that may advect in from from the east and heights should gradually lower back toward 590-594dm after next Monday. Either way, there is enough confidence to issue an Excessive Heat Watch starting Friday for the south-central Arizona deserts spreading nearly all other areas for next Saturday through Monday. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major weather aviation impacts to consider. Few-Sct CU developing so far this afternoon over the eastern mountains but should stay well out of the terminal area. Winds otherwise follow their typical W/SW direction around 10-15kts for all TAF sites with some afternoon gustiness around 20-25kts possible. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Wednesday through Sunday... Dry air will dominate the region through the weekend as strong high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Wednesday increasing to at least 10F above average (record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Excessive Heat Watch from Friday morning through Monday evening for AZZ022-023-027-028. Excessive Heat Watch from Saturday morning through Monday evening for AZZ020-021-024>026. CA...Excessive Heat Watch from Saturday morning through Monday evening for CAZ031>033. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Kuhlman CLIMATE...MO AVIATION...MO FIRE WEATHER...Deemer
  [top] Area Forecast Discussion National Weather Service Tucson AZ 131 PM MST SUN JUN 12 2016 .SYNOPSIS...Generally dry conditions are forecast through next weekend. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures will return during the latter half of the week and especially next weekend. && .DISCUSSION...Cumulus clouds from Tucson east to the New Mexico border are fairly flat today since the atmosphere has stabilized due to the decreased moisture. Could be a stray sprinkle or wind gust underneath these clouds near the state line but the forecast is essentially dry. On Monday a trough of low pressure will pass to our north. The trough will enhance lift, but there will be even less moisture to act on, and thus have kept the forecast for southeast AZ dry Monday. The trough will bring increased southwest winds Monday afternoon with gusts 30-35 mph possible, especially in Cochise County. In addition, high temperatures will be a couple of degrees cooler. Daytime temperatures will then begin a warming trend into next weekend, when longer range models indicate very hot temperatures similar to or even warmer than what we saw June 4-6. On the bright side, drier air will allow temperatures to drop to more comfortable levels beginning Monday night compared to the past few nights. This trend should hold for much of the work week, especially east of Tucson. && .AVIATION...VALID THRU 14/00Z. Scattered to broken clouds from 10-12k ft msl east of KTUS with generally clear skies for the western deserts. Skies becoming mostly clear area-wide after sunset. Surface winds W/SW this afternoon at 10-18 kts with gusts to 25 kts, then diminishing after sunset to less than 10 kts. W/SW winds of 10-20 kts with gusts of 25-30 kts possible. Highest wind gusts will be near KDUG. Winds will increase again after 18z Monday. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Dry conditions will prevail through next weekend. A weather system traversing across northern Arizona will result in below normal daytime temperatures through Tuesday. In addition, some afternoon breezes are expected each afternoon this week. A few spots could briefly approach critical thresholds Monday afternoon across Southeast Cochise County. Otherwise, hotter temperatures will return by the middle of the week, then especially by next weekend with very well above normal temperatures and possible Haines 6 conditions. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ KD/GL Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion National Weather Service Flagstaff AZ 1009 AM MST SUN JUN 12 2016 .SYNOPSIS...Dry and breezy conditions are forecast today, with a few thunderstorms possible near the New Mexico state line. A slight chance of thunderstorms exists north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. Record high temperatures look to make a return by next weekend. && .UPDATE/DISCUSSION... Isolated thunderstorms were added to areas near the New Mexico state line, mainly through 2-3 pm MST. Cumulus can be seen on satellite in far eastern Arizona, as well as most of western New Mexico. Moisture/instability should decrase later this afternoon as the trough pushes east with time today. Expect a dry and breezy afternoon across most of northern Arizona. The strongest winds are forecast across the Coconino Plateau northwest of Flagstaff, with a few wind gusts in excess of 35 mph possible. && .PREV DISCUSSION /251 AM MST/...Breezy conditions are expected across northern Arizona this afternoon as an upper-level trough, currently just off the southern California coast, slowly makes its way eastward. Ample dry air throughout the lower and upper levels of the atmosphere should prevent any precipitation from developing today. Monday...As the trough swings through the region, there will be enough moisture/instability for a few showers and storms to develop during the late morning and afternoon hours, mainly north of I-40. The best chances will be along and north of a line from the Grand Canyon to Window Rock. Tuesday through Friday...Dry weather is expected through this period along with a warming trend as high pressure begins to build into the area. High temperatures will rise to 5 to 10 degrees above normal by Friday. Additionally, breezy southwest winds may make for near critical to critical fire weather conditions on Wednesday and Thursday. Saturday and Sunday...All the major global models are in agreement with a very strong ridge of high pressure settling over Arizona. This is still a week out, so the exact strength and placement of the high is subject to change. However, early signs point to record high temperatures returning to Arizona. This ridge is forecast to be even stronger than the last one that brought record temperatures to the state. The NAEFS and GEFS mean have this ridge in the 99th to 100th percentile, meaning the models are expecting this ridge to be abnormally strong, even for June. The current forecast is calling for temperatures to generally be 10 to 15 degrees above normal. && .AVIATION...For the 18Z Package...A drier air mass will bring mainly VFR conds over the next 24 hrs. There will be a isold shra/tsra mainly across portions of Apache Co. mainly along the Arizona/New Mexico border from 18z today - 03z Monday. Afternoon SW winds 10-20 kts gusting to 30 kts dcrsg aft sunset. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A drier air mass will move over Arizona today with isolated thunderstorms near the Arizona/New Mexico border. Near- critical fire weather conditions are forecast this afternoon over portions of Coconino and northwest Yavapai counties. On Monday, a few isolated showers possible along and north of Interstate 40 with the passage of a weather disturbance. Tuesday through Thursday...Dry southwesterly flow will dominate the weather across Arizona with afternoon humidity values potentially dropping into the single digits and gusty winds each day. Critical fire weather conditions will be possible. .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Taylor/Mottice AVIATION...TC FIRE WEATHER...TC/McCollum For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 1009 AM MST SUN JUN 12 2016 .SYNOPSIS...Dry and breezy conditions are forecast today, with a few thunderstorms possible near the New Mexico state line. A slight chance of thunderstorms exists north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. Record high temperatures look to make a return by next weekend. && .UPDATE/DISCUSSION... Isolated thunderstorms were added to areas near the New Mexico state line, mainly through 2-3 pm MST. Cumulus can be seen on satellite in far eastern Arizona, as well as most of western New Mexico. Moisture/instability should decrase later this afternoon as the trough pushes east with time today. Expect a dry and breezy afternoon across most of northern Arizona. The strongest winds are forecast across the Coconino Plateau northwest of Flagstaff, with a few wind gusts in excess of 35 mph possible. && .PREV DISCUSSION /251 AM MST/...Breezy conditions are expected across northern Arizona this afternoon as an upper-level trough, currently just off the southern California coast, slowly makes its way eastward. Ample dry air throughout the lower and upper levels of the atmosphere should prevent any precipitation from developing today. Monday...As the trough swings through the region, there will be enough moisture/instability for a few showers and storms to develop during the late morning and afternoon hours, mainly north of I-40. The best chances will be along and north of a line from the Grand Canyon to Window Rock. Tuesday through Friday...Dry weather is expected through this period along with a warming trend as high pressure begins to build into the area. High temperatures will rise to 5 to 10 degrees above normal by Friday. Additionally, breezy southwest winds may make for near critical to critical fire weather conditions on Wednesday and Thursday. Saturday and Sunday...All the major global models are in agreement with a very strong ridge of high pressure settling over Arizona. This is still a week out, so the exact strength and placement of the high is subject to change. However, early signs point to record high temperatures returning to Arizona. This ridge is forecast to be even stronger than the last one that brought record temperatures to the state. The NAEFS and GEFS mean have this ridge in the 99th to 100th percentile, meaning the models are expecting this ridge to be abnormally strong, even for June. The current forecast is calling for temperatures to generally be 10 to 15 degrees above normal. && .AVIATION...For the 18Z Package...A drier air mass will bring mainly VFR conds over the next 24 hrs. There will be a isold shra/tsra mainly across portions of Apache Co. mainly along the Arizona/New Mexico border from 18z today - 03z Monday. Afternoon SW winds 10-20 kts gusting to 30 kts dcrsg aft sunset. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A drier air mass will move over Arizona today with isolated thunderstorms near the Arizona/New Mexico border. Near- critical fire weather conditions are forecast this afternoon over portions of Coconino and northwest Yavapai counties. On Monday, a few isolated showers possible along and north of Interstate 40 with the passage of a weather disturbance. Tuesday through Thursday...Dry southwesterly flow will dominate the weather across Arizona with afternoon humidity values potentially dropping into the single digits and gusty winds each day. Critical fire weather conditions will be possible. .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Taylor/Mottice AVIATION...TC FIRE WEATHER...TC/McCollum For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 912 AM MST SUN JUN 12 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border this afternoon followed by dry condiitons Monday through next weekend. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through next weekend. && .DISCUSSION...Just a bit moisture hanging on near the New Mexico border, and what is left should be scrubbed out by southwest flow by sunset. Could be a few cloud buildups over the higher terrain east of Tucson this afternoon and just maybe a stray thunderstorm over the White Mountains, so going forecast looks good. Valley high temps in the 90s today will feel a bit better than the past few days since the humidity will be much lower. These temperatures are still a bit below average for June 12th. As mentioned in the previous discussion, it will be getting hotter by the end of the new work week. && .AVIATION...VALID THRU 13/18Z. Scattered clouds from 10-12k ft msl near the New Mexico border this afternoon with slgt chc of -shra/-tsra, otherwise SKC. Surface winds less than 10 kts...then becoming W/SW this afternoon at 10-18 kts with gusts to 25 kts. Wind diminishing after sunset to less than 10 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...A slight chance of thunderstorms near the New Mexico border this afternoon. Dry conditions will then prevail Monday through next weekend. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .PREV DISCUSSION...The pre-Monsoon thunderstorm action of the past two days is coming to an end. A few storms are still possible near the New Mexico border today otherwise drier air continues to push in from the west over the area. Cooler than normal temperatures today into Tuesday then a warming trend during the second half of the work week with the furnace being turned on next weekend. Models consistent on developing a very strong high pressure ridge over the area next weekend with 500 mb heights approaching 600 DM. Based on in house low level thickness value study highs next weekend have the potential to be hotter than what occurred earlier this month and will approach record highs on the 17th thru the 19th. Could end up being historic as some places may end up close to not only all-time June record highs but all- time yearly record highs. A little early for issuance of an excessive heat watch but will be getting the message out via social media platforms today. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ KD Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion National Weather Service Phoenix AZ 848 AM MST SUN JUN 12 2016 .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Considerable drying has occurred over the past 24 hours with PWATS falling to well below an inch. Given the drop in moisture levels there is now little to no chance of any additional shower or thunderstorm activity. Skies will remain clear aside from a few mid level afternoon CU mainly focused over the south-central Arizona higher terrain. A slow moving upper level trough currently off the Southwest U.S. coast will move into the region tonight into Monday, but no additional moisture will be added, so the only result will be the continued slightly below normal temperatures. I made some minor adjustments to sky cover to add in more areal CU coverage for this afternoon. The rest of the forecast is on track with no other adjustments are needed. && .PREVIOUS DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather impacts through Monday morning with only Few-Sct CU developing over the mountains this afternoon. Winds around central Arizona may obtain a cross runway southerly component near 10kt for a few hours late this morning before veering to the more traditional W/SW direction. A few gusts 20-25kt will be possible, but confidence in prolonged stronger gusts is low. Across SE CA, winds will favor a S/SW type direction though may be light and variable on occasion. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate the region through the weekend as high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Tuesday and Wednesday increasing to at least 10F above average (and near record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Kuhlman PREVIOUS DISCUSSION...Hernandez CLIMATE...MO AVIATION...MO FIRE WEATHER...MO/Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 440 AM MST SUN JUN 12 2016 ...Updated Aviation and Fire Weather... .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .CLIMATE... Record high temperatures late this week through early next week: Date Phoenix Yuma ---- ------- ---- June 18 115 in 2015 116 in 2015 June 19 115 in 1968 115 in 1960 June 20 115 in 1968 116 in 2008 && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather impacts through Monday morning with only Few-Sct CU developing over the mountains this afternoon. Winds around central Arizona may obtain a cross runway southerly component near 10kt for a few hours late this morning before veering to the more traditional W/SW direction. A few gusts 20-25kt will be possible, but confidence in prolonged stronger gusts is low. Across SE CA, winds will favor a S/SW type direction though may be light and variable on occasion. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate the region through the weekend as high pressure builds back over the region. As a result, minimum humidity levels will generally fall into the single digits each afternoon while fair overnight recovery becomes poor by the weekend. Temperatures will also increase substantially with near normal temperatures Tuesday and Wednesday increasing to at least 10F above average (and near record highs) by Saturday. Winds will remain fairly typical for mid June, with some afternoon gusts approaching 20 to 25 mph in the usual upslope favored locations. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hernandez CLIMATE...MO AVIATION...MO FIRE WEATHER...MO/Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 309 AM MST SUN JUN 12 2016 .SYNOPSIS... A low pressure system will move across the region through mid-week, keeping temperatures near normal. Precipitation chances will be almost non-existent as drier air continues to filter into southeast California and southern Arizona. A warming trend will dominate during the latter half of the week leading to excessively hot conditions by next weekend. && .DISCUSSION... Currently, a fuller latitude trough is centered over the US West Coast and effectively enveloping the local forecast area under dryslot subsidence, which is evident in current water vapor imagery. As a result, precipitation chances have also ended. Forecast models through the first half of the week remain in good agreement that the aforementioned East Pacific trough will continue to slowly move across the SW Conus and be the primary influence on weather and temperatures. As the southern portion of this trough advances towards our CWA, there will be demonstrable dynamic forcing. However, any notable moisture will have been pushed far downstream of our area such that the precipitation threat over southern Arizona and southeast California will be almost non-existent. The only impact this system will have in our CWA will be temperatures slightly lowering to a near normal range with highs in the 90s to lower 100s through Tuesday. This "cooler" weather doesn`t last for long. For the remainder of the period, a blocking pattern will keep a strong amplified ridge over the SW US with the GFS and the ECMWF indicating H5 heights increasing from 584-588dm on Wednesday to 598-600dm Sunday. Even the NAEFS mean temperatures and geopotential heights output is indicating heights and temperatures aloft at or above the 99th percentile. Therefore, as this warming trend continues during the latter half of the week, high temperatures will rise from 95F-105F on Wednesday to 115F to 120F degrees by Sunday. Given such high confidence, an Excessive Heat Watch or Warning for next weekend will likely be issued within the next couple days. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hernandez AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Flagstaff AZ 251 AM MST SUN JUN 12 2016 .SYNOPSIS...Dry and breezy conditions are forecast today, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. Record high temperatures look to make a return by next weekend. && .DISCUSSION...Breezy conditions are expected across northern Arizona this afternoon as an upper-level trough, currently just off the southern California coast, slowly makes its way eastward. Ample dry air throughout the lower and upper levels of the atmosphere should prevent any precipitation from developing today. Monday...As the trough swings through the region, there will be enough moisture/instability for a few showers and storms to develop during the late morning and afternoon hours, mainly north of I-40. The best chances will be along and north of a line from the Grand Canyon to Window Rock. Tuesday through Friday...Dry weather is expected through this period along with a warming trend as high pressure begins to build into the area. High temperatures will rise to 5 to 10 degrees above normal by Friday. Additionally, breezy southwest winds may make for near critical to critical fire weather conditions on Wednesday and Thursday. Saturday and Sunday...All the major global models are in agreement with a very strong ridge of high pressure settling over Arizona. This is still a week out, so the exact strength and placement of the high is subject to change. However, early signs point to record high temperatures returning to Arizona. This ridge is forecast to be even stronger than the last one that brought record temperatures to the state. The NAEFS and GEFS mean have this ridge in the 99th to 100th percentile, meaning the models are expecting this ridge to be abnormally strong, even for June. The current forecast is calling for temperatures to generally be 10 to 15 degrees above normal. && .AVIATION...For the 12Z Package...A drier air mass will bring mainly VFR conditions over the next 24 hours. There will be a slight chance of showers and thunderstorms across the area of the Arizona/New Mexico border. Afternoon Southwest winds 10-20 kts gusting to 30 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A drier air mass will move over Arizona today with just a slight chance of showers and thunderstorms near the Arizona/New Mexico border. On Monday, a few isolated showers possible along and north of Interstate 40 with the passage of a weather disturbance. Southwest winds in the 10 to 20 mph range each afternoon. Tuesday through Thursday...Dry southwesterly flow will dominate the weather across Arizona with afternoon humidity values potentially dropping into the single digits and gusty winds each day. Critical fire weather conditions will be possible. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Mottice AVIATION...McCollum FIRE WEATHER...McCollum For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 235 AM MST SUN JUN 12 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border this afternoon followed by dry condiitons Monday through next weekend. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through next weekend. && .DISCUSSION...The pre-Monsoon thunderstorm action of the past two days is coming to an end. A few storms are still possible near the New Mexico border today otherwise drier air continues to push in from the west over the area. Cooler than normal temperatures today into Tuesday then a warming trend during the second half of the work week with the furnace being turned on next weekend. Models consistent on developing a very strong high pressure ridge over the area next weekend with 500 mb heights approaching 600 DM. Based on in house low level thickness value study highs next weekend have the potential to be hotter than what occurred earlier this month and will approach record highs on the 17th thru the 19th. Could end up being historic as some places may end up close to not only all-time June record highs but all-time yearly record highs. A little early for issuance of an excessive heat watch but will be getting the message out via social media platforms today. && .AVIATION...VALID THRU 13/12Z. Scattered clouds from 10-12k ft msl near the New Mexico border this afternoon with slgt chc of -shra/-tsra, otherwise SKC. Surface winds less than 10 kts...then becoming W/SW this afternoon at 10-18 kts with gusts to 25 kts. Wind diminishing after sunset to less than 10 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...A slight chance of thunderstorms near the New Mexico border this afternoon. Dry conditions will then prevail Monday through next weekend. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Phoenix AZ 929 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next few days keeping temperatures near to slightly below normal. Drier air will keep southern Arizona and southeast California dry. A warming trend takes hold during the latter half of the week leading to excessively hot conditions next weekend. && .DISCUSSION... Earlier Storm activity ended mainly before sunset due to drier air moving into the region. The drying trend is evident in the 00Z soundings. Also evident in the water vapor imagery (though it doesn`t depict shallow moisture well since it`s more sensitive to higher/colder regions of the atmosphere). Speaking of water vapor imagery, there is a well defined upper low centered just off the southwest CA coast. This feature is within the southern branch of a larger upper trough - the brunt of which is over western Canada and the northwest CONUS. Downstream of the trough is a high amplitude ridge. The trough has already started to spread drier air over the forecast area and will continue to do that overnight. This will end any precip chances. As the southern portion of the trough advances inland, there will be a minor increase in moisture on Monday but not enough for any precip threat over southern AZ and/or southeast CA. Otherwise, there will be very little discernible impact on the sensible weather - perhaps very slight cooling Monday. This is because the system is weakening as it moves inland. Plus the air will be drier than it has been the past couple days. Thereafter, it`s a warming trend. Forecasts in good shape. No changes at this time. && .PREVIOUS DISCUSSION...issued 224 pm MST/PDT... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Weak upper low centered near southwest CA coast spreading dry air over the deserts for an end to the storm activity tonight through Sunday with clear skies. Surface winds tonight and Sunday will largely be a repeat of pattern from past 24 hours. An exception is the Imperial Valley with westerly winds prevailing tonight through Sunday. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...AJ PREVIOUS DISCUSSION...Nolte/MO AVIATION...AJ FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Tucson AZ 909 PM MST SAT JUN 11 2016 .SYNOPSIS...A few thunderstorms may occur near the New Mexico border Sunday followed by dry condiitons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Showers and thunderstorms that developed this afternoon across parts of southeast Arizona have ended late this evening. Still looking at some debris cloudiness east of Tucson, with clear skies elsewhere. General clearing will continue overnight tonight, with a few cloud build ups and isolated thunderstorms near the New Mexico border tomorrow afternoon. Current forecast handled these trends well, so no updates expected this evening. && .AVIATION...VALID THRU 13/06Z. Cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .PREV DISCUSSION...11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 853 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated showers will continue over northern Coconino county through Saturday evening. Otherwise...dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 on Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Convection is rapidly decreasing this evening...with isolated showers expected til midnight over N. Coconin county. Grids are in great shape, and no updates are planned at this time. && .PREV DISCUSSION.../323pm mst/...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 06Z Package...VFR conditions expected through Sunday...with southerly winds gusting to 30kts Sunday afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM/BAK AVIATION/FIRE WEATHER...Bohlin/BAK For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 330 PM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...Scattered showers and thunderstorms were ongoing mostly north-to-east of the Tucson metro area this afternoon. Various 11/12Z NWP models suggest the bulk of these showers and thunderstorms will gradually decrease in coverage and intensity during the next several hours. Expect isolated to scattered showers and thunderstorms mainly from Tucson east to the New Mexico border this evening. A slight chance of showers and thunderstorms then continues late tonight into Sunday evening mainly near the New Mexico border. 11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper trough over the desert southwest Monday. Stronger swly flow aloft Monday will push deeper moisture well newd into the central/srn Rockies and adjacent high plains. Precip-free conditions will commence Monday, and dry conditions will continue Tuesday into next weekend as high pressure aloft gradually amplifies during the latter part of the upcoming week. The GFS/ECMWF were quite similar with the depiction of at least a 597 dm high to be centered over ern Arizona/ wrn New Mexico by next Saturday. The upshot...high temps thru Tue will generally a few degs or so below normal, then hotter temps will prevail Fri-Sat. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity nwd/ewd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight thru Sunday afternoon. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson northward, and eastward to the New Mexico border. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through next Saturday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next weekend. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion...UPDATED National Weather Service Flagstaff AZ 323 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend. && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers and thunderstorms will diminish this evening around sunset. On Sunday drier air moves in ending chances for thunderstorm activity while southwest 20FT winds will increase to a sustained 15 to 20 mph range. Monday a few isolated showers possible along and north of Interstate 40. Tuesday through Thursday...High pressure builds in from Tuesday onward with hot and dry weather in the extended forecast. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION/FIRE WEATHER...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 308 PM MST SAT JUN 11 2016 .SYNOPSIS...Isolated to scattered thunderstorms will continue over northern Yavapai and western Coconino counties through the late afternoon hours. Dry and breezy conditions are forecast Sunday, with a slight chance of thunderstorms north of I-40 Monday. A drying/warming trend will commence Tuesday, and will continue through the end of next weekend (June 19). && .DISCUSSION...Isolated to scattered thunderstorms continue to develop over northern Yavapai and western Coconino counties where MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep layer shear is keeping this convection disorganized and well below severe limits. This activity should continue through the late afternoon hours, then begin to wane around sunset with the loss of daytime heating. By Sunday, an upper level trough will sag just west of the Baja Peninsula. Models prog Arizona to get dry slotted with little to no convection anticipated. However, given the proximity of the trough and subsequent height gradient, breezy to windy conditions are forecast over northern Arizona. Winds should remain below advisory levels. Monday, the aforementioned trough will weaken as it lifts north over Arizona. The best upper forcing should remain confined to areas north of I-40. Upper dynamics (albeit weak) combined with lingering moisture and instability should be sufficient to warrant a slight chance of Monday afternoon thunderstorms north of I-40. Tuesday through Saturday, an upper level ridge will build over the southwestern United States. This will lead to a drying and warming trend over Arizona through next weekend (June 19). && .AVIATION...For the 00Z Package...Southerly flow and lingering moisture will allow for continued isolated to scattered showers and thunderstorms for the rest of the afternoon. After 02Z showers and thunderstorms will diminish. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Phoenix AZ 224 PM MST SAT JUN 11 2016 .SYNOPSIS... High pressure will be displaced to the east over the next several days resulting in somewhat cooler weather through early next week. Showers and thunderstorms will also be pushed well east as drier air moves back into the region. After several relatively comfortable days with near normal temperatures through the middle of next week, excessively hot weather will likely settle back into the area by the end of next week. && .DISCUSSION... As earlier thought, storm activity did form over portions of south- central and southeast AZ over the last few hours...just not over the Rim and White Mtns but the along the foothills/mountains across Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis, Suominet PWV and TPW satellite imagery indicated the main PWAT axis/concentration south of the Phoenix Metro and storms still persist across portions of Pinal County at time of writing. South to southwesterly steering flow aloft has lofted debris cirrus over the Phoenix area and for the time being, stabilized the area enough to prevent any northward advancement of the remaining isolated storms over the open deserts to the south. Early afternoon IR imagery depicts a clear boundary between the drier and better mixed portions of far southwest AZ and southeast CA and the storms/debris clouds over south-central AZ. Storms so far today managed to form in a slight deformation zone aloft as flow further to the west begins to turn ahead of an approaching upper trough and then splits over central AZ with the expansive anticyclonic flow over the central CONUS. For the rest of this evening, still favorable mixed-layer CAPE surface and upper difluence will allow for additional isolated storm development east of the areas where storms formed so far today. Cannot rule out a thundershower or two making their way northward into the Phoenix-metro through 6pm or so, otherwise we`ll remain under the debris cloudiness and occasional outflow driven breezes. Conditions will continue to further mix out across the western forecast zones as drier air is advected into the area with continued breezy south winds. Activity should quickly dissipate after sunset and loss of daytime heating, with clouds continuing to stream north/northeastward before clearing out overnight. Forecast models during the first half of next week remain in good agreement that a modest cold core trough will pass through the Southwest keeping H5 heights temporarily in a 580-588dm range. Although dynamic forcing with this system looks to be ample, any better quality moisture will have been repositioned downstream of southeast California and Arizona. This should be true for the entire atmospheric column, and little other than a brief frontal cloud band would be anticipated. However, the benefit from this system will be temperatures hovering in a near normal range with highs only in the upper 90s to lower 100s. Unfortunately, the western hemisphere flow pattern will become far more blocked and amplified during the latter half of next week and through the weekend. With mean negative height anomalies roughly centered over the NE Pacific and northern Quebec, strong ridging will build throughout the intermountain west. Not only is there seasonal preference for this configuration, but essentially every NAEFS member indicates an almost identical pattern yielding excellent forecast confidence. The biggest question will be how warm it gets as the 00Z operational GFS and handful of ensemble members indicate H5 heights eclipsing the 600dm threshold over the four corners next weekend. Regardless, NAEFS mean output for next weekend already suggests heights/temperatures aloft in the 99th percentile, and its not atypical for the warmer extreme parts of an ensemble system to verify this time of year. Thus, its already a very good bet that excessive heat and afternoon highs at least 115F will return by the end of next week; and not out of the question if the GFS type heights come to fruition that someone could be making a run at the 120F mark sometime next weekend. && .AVIATION... South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast California/Southwest Arizona including KIPL and KBLH: Isolated showers and thunderstorms should only impact areas south of the Phoenix metro through the rest of the afternoon, but confidence is not high enough to totally rule a shower or storm to briefly affect southern portions of the metro area. Breezy southerly winds will eventually turn westerly this evening for the Phoenix terminals and remain westerly through much of the overnight. After midnight the area will be under drying conditions and clearing skies. Gusty southerly winds will affect southeast California including KBLH and KIPL through around midnight with winds 10 kts or less thereafter. Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Tuesday through Saturday... Dry air will dominate through the forecast period as high pressure builds back over the region. As a result, minimum humidities over the lower deserts will generally fall in the single digits each afternoon. Temperatures will also be on the rise, with near normal temperatures Tuesday, becoming warmer than average on Wednesday with continued warming into the early part of the weekend. High temperatures across the deserts will reach above 110 degrees starting Saturday. Winds will generally be light, but afternoon breeziness will be common with some gusts approaching 20 15 mph. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Nolte/MO AVIATION...Kuhlman FIRE WEATHER...Kuhlman
Area Forecast Discussion National Weather Service Flagstaff AZ 1218 PM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Convection is firing over the higher terrain of Yavapai county and western Coconino county early this afternoon. Thunderstorm activity is also developing over southern Apache county in the vicinity of the White Mountains. Think the convection over Yavapai/western Coconino counties will expand in coverage this afternoon due to increasing instability. Updated the forecast to expand scattered coverage of afternoon thunderstorms into the North Rim area based on current obs/trends. The remaining weather elements are in good shape. The updated forecast has been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with scattered coverage over Yavapai and western Coconino counties. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Flagstaff AZ 935 AM MST SAT JUN 11 2016 .SYNOPSIS...Drier southwest flow returns later today and especially Sunday, with breezy conditions and decreasing shower activity. A chance of showers and thunderstorms continues on Monday with a passing trough, before a strong warming and drying trend for the remainder of next week. && .UPDATE...Current visible satellite imagery shows convective clouds beginning to develop over Yavapai and western Coconino counties. Furthermore, a mid/high level cloud deck over most of Navajo and all of Apache counties should continue to lift north of the region through the afternoon. The latest high-res models prog increasing instability over Yavapai and western Coconino counties today. Furthermore, with dewpoints in the upper 40s and 50s, think enough lift and instability should initiate convection along the Mogollon Rim this afternoon. Weak deep layer shear should keep convection below severe limits. Updated the forecast based on current obs/trends. Increased the temporal resolution of pops in order to try and best time the convection across northern Arizona this afternoon. Otherwise, the remaining forecast is on track. The updated products have been sent. && .PREV DISCUSSION /346 AM MST/... Low pressure off the southern California coast will approach Arizona over the coming days, eventually crossing the state on Monday. In the meantime, chances for showers will continue again today, though expected to be less widespread than we experienced on Friday. Even less activity is likely for Sunday, though gustier southwest winds are anticipated. Monday appears to be our last chance for showers in the 7-day forecast as the trough passes across the region. In the wake of the passing trough, drier air and much warmer daytime temperatures will return under strengthening high pressure. && .AVIATION...For the 18Z Package...Southerly flow and lingering moisture will allow for isolated to scattered showers and thunderstorms today. Wind gust up to 35 kts possible with storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect showers and thunderstorms to develop this afternoon with isolated coverage in northwestern Arizona and more scattered coverage in northeastern Arizona. On Sunday drier air moves in ending chances for thunderstorm activity. Monday through Wednesday...A weak disturbance brings isolated showers and a few thunderstorms to the northern third of the state. High pressure builds in from Tuesday onward with hot and dry weather. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...TM AVIATION...Bohlin For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 915 AM MST SAT JUN 11 2016 .SYNOPSIS...Expect scattered showers and thunderstorms from Tucson eastward into this evening. A few thunderstorms may occur near the New Mexico border Sunday followed by dry conditons Monday through Friday. Daytime temperatures will remain near normal or a few degrees below normal through Tuesday, then hotter temperatures return Wednesday through Friday. && .DISCUSSION...11/12Z Univ of AZ WRF-NAM and several HRRR solutions suggest that showers/tstms will develop near the Tucson metro area eastward/southward later this morning into early this afternoon. These cells will then move quickly nwd/newd, with the main concern for potentially damaging wind gusts. The bulk of these showers/ tstms will end this evening. There are no updates planned at this time. Please refer to the additional sections for further detail. && .AVIATION...VALID THRU 12/18Z. Isolated to scattered TSRA/SHRA from KTUS vicinity ewd/swd into this evening, then isolated -TSRA/-SHRA mainly near the New Mexico border late tonight into Sunday morning. Brief wind gusts to around 45 kts will occur with the stronger thunderstorms. Otherwise, cloud decks from Tucson eastward will range from 7k-10k ft msl. Clear skies or scattered clouds above 15k ft msl west of KTUS into Sunday morning. Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25 kts. Surface wind mainly less than 10 kts at other times except near thunderstorms. Aviation discussion not updated for TAF ammendments. && .FIRE WEATHER...Expect scattered thunderstorms into this evening, especially from Tucson east and south. Isolated thunderstorms Sunday afternoon will occur mostly near the New Mexico border. Dry conditions will then prevail Monday through Friday. Daytime temperatures will be a few degrees below normal into early next week, then hotter temperatures return Wednesday into next Friday. && .PREV DISCUSSION /234 AM MST/...Precipitable water values remain well above mid-June normals this morning with values mostly in the 1.00"-1.50" range. Water vapor imagery showed an upper level low approaching southern CA. Drier air will start to push in from the west as the day progresses, but enough will be around across the eastern 2/3rds of the area for isolated valley/scattered mountains showers and thunderstorms. Precipitable water values are forecast to be below 1" on Sunday with a slight chance of storms relegated to the White mountains. High temperatures this weekend will remain several degrees below normal. Upper level trof will push across the state on Monday providing slightly cooler daytime temperatures and further drying of the atmosphere. Upper ridge strengthens over the area Tuesday through Friday resulting in warmer daytime high temperatures. Outside of this forecast package are likely hotter daytime temperatures as the upper ridge continues to strengthen over the area. Highs next weekend could rival what occurred earlier this month. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1042 AM PDT SUN JUN 12 2016 .SYNOPSIS... Low pressure will bring mostly cloudy skies to most of the area today along with morning drizzle. There is a slight chance of a mountain thunderstorm today. The morning low cloud pattern will slowly diminish through the week. A significant heat wave is possible later next weekend into early next week. && .SHORT TERM...(TDY-TUE) Main forecast concerns for today will be the deep marine layer clearing of the stratus (or lack thereof), along with the slight chance of thunderstorms over the Ventura/SBA County mountains. The slight chance of thunderstorms for the areas mentioned above still looks warranted, with the NAM showing around 1000 J/kg of CAPE. The NAM doesn`t spit out any QPF in these areas, but the GFS and HRRR hint at some convective precip late this afternoon. No mention of thunderstorms over the San Gabriel Mountains in the official forecast, but it`s not inconceivable for something to develop there this afternoon, with the NAM showing decent instability in this area as well. Thinking that the most likely scenario will be some buildups, with possibly a shower over the Ventura/SBA mountains, but likely no thunder. No changes were made to the thunderstorm forecast. Latest soundings indicated a marine layer close to 5000 ft deep. With the deep marine layer and a strong eddy in place, updated the sky forecast for today to keep the coast/valley areas from SBA to LA mostly cloudy all day, although there could be a few break of sun later this afternoon. There will also continue to be some patchy drizzle, but any measurable amounts should remain mostly confined to the foothills. No other changes were made to the forecast. There will once again be some local advisory level wind gusts today in the Antelope Valley with strong onshore flow. After today, the main forecast concern will continue to be the possibility of a major heat wave next weekend into the following week. Also the possibility of a weak sundowner Tuesday night. ***FROM PREVIOUS DISCUSSION*** Still plenty of low clouds on Monday...but the marine inversion will be weaker as the result of the low passage and this will allow for better clearing everywhere xcp the beaches. There is a slight chc that this is the wrong idea and that the marine layer will be so deep and the upper inversion not strong enough to hold the clouds together...if this comes true then there will be reverse clearing which will bring sunny skies to the coasts and mostly cloudy skies to the vlys. Broad weakly cyclonic flow assoc with a cool pac NW upper low moves over the state on Tuesday. This will result in a typical marine layer pattern with the morning clouds and a sunny afternoon. Max temps will be well blo normal today and Monday due to the onshore flow extensive clouds. Max temps will rebound slightly Tuesday with the higher hgts and greater sunshine but they will remain blo normal. .LONG TERM...(WED-SAT) Not much excitement for Wednesday and Thursday. The upper low moves down the Oregon coast and tilts the flow over Srn Ca into a more SW to NE orientation. There will not be much change in the weather from Tuesday on both days. Look for typical night through morning low clouds and fog pattern with max temps close to normal. The real story of the xtnd fcst is the Friday through Sunday portion. A large upper high will slowly press westward through the period hgts will rise through the period from 582 DM on Friday to 594 DM on Sunday. The onshore flow will weaken and the marine layer clouds will diminish. Max temps will rise each day. On Friday max temps will be 1 to 3 degrees above normal and by Sunday max temps will 10 to 20 degrees above normal. Next Monday looks warmer still. This could unfold into a major heat event and people should monitor the forecast for the latest developments. && .AVIATION...12/18Z... Mid/upper level trough of low pressure over the area will shift east. Upper level moderate south winds will become moderate northwest while mid level light south winds become light north- northwest after 13/05z. Isolated thunderstorms are possible over the Ventura and Santa Barbara county mountains between 12/20-13/02z with tops 32kft and will move east 10kt or less. Weak to moderate onshore pressure gradient through the period. Weak capping marine inversion with organized cloud tops approximately 5kft this morning will continue weak with disorganized cloud tops between 2-4kft Monday morning. Marine layer at LAX at 1400Z is 4995 feet deep and the inversion top is at 5850 feet with a temp of 10.7 degrees C. KLAX...Chance cigs 035-040 through 13/09z then chance cigs 028 between 13/09-13/20z. KBUR...Chance cigs 019 through 12/20z then chance cigs 035 12/20-13/04z. Chance cigs 024-030 after 13/04z. virtually certain - 95-100% very likely - 80-95% likely - 60-80% chance - 30-60% very unlikely - 20% OR LESS && .MARINE...12/200 PM... Small craft advisory conditions for winds are not expected through Monday morning. Northwest winds are expected to develop and increase Monday afternoon and there is a chance small craft advisory conditions will exist at times from Piedras Blancas to San Nicolas island Monday night through Friday. Northwest locally generated seas will build to around 10 feet from Piedras Blancas to San Nicolas island Tuesday and subside below 10 feet Wednesday evening. Otherwise an active storm track over the Southern Ocean last week had generated seas within 190-220 degrees relative to Ventura. The swells will build near shore through the week. Small craft advisory for hazardous sea conditions area not expected but extra currents and surging along exposed south facing shores are likely. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...Sukup AVIATION...30 MARINE...30 SYNOPSIS...Sweet weather.gov/losangeles
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
940 AM PDT SUN JUN 12 2016 .SYNOPSIS... Low pressure will bring mostly cloudy skies to most of the area today along with morning drizzle. There is a slight chance of a mountain thunderstorm today. The morning low cloud pattern will slowly diminish through the week. A significant heat wave is possible later next weekend into early next week. && .SHORT TERM...(TDY-TUE) Main forecast concerns for today will be the deep marine layer clearing of the stratus (or lack thereof), along with the slight chance of thunderstorms over the Ventura/SBA County mountains. The slight chance of thunderstorms for the areas mentioned above still looks warranted, with the NAM showing around 1000 J/kg of CAPE. The NAM doesn`t spit out any QPF in these areas, but the GFS and HRRR hint at some convective precip late this afternoon. No mention of thunderstorms over the San Gabriel Mountains in the official forecast, but it`s not inconceivable for something to develop there this afternoon, with the NAM showing decent instability in this area as well. Thinking that the most likely scenario will be some buildups, with possibly a shower over the Ventura/SBA mountains, but likely no thunder. No changes were made to the thunderstorm forecast. Latest soundings indicated a marine layer close to 5000 ft deep. With the deep marine layer and a strong eddy in place, updated the sky forecast for today to keep the coast/valley areas from SBA to LA mostly cloudy all day, although there could be a few break of sun later this afternoon. There will also continue to be some patchy drizzle, but any measurable amounts should remain mostly confined to the foothills. No other changes were made to the forecast. There will once again be some local advisory level wind gusts today in the Antelope Valley with strong onshore flow. After today, the main forecast concern will continue to be the possibility of a major heat wave next weekend into the following week. Also the possibility of a weak sundowner Tuesday night. ***FROM PREVIOUS DISCUSSION*** Still plenty of low clouds on Monday...but the marine inversion will be weaker as the result of the low passage and this will allow for better clearing everywhere xcp the beaches. There is a slight chc that this is the wrong idea and that the marine layer will be so deep and the upper inversion not strong enough to hold the clouds together...if this comes true then there will be reverse clearing which will bring sunny skies to the coasts and mostly cloudy skies to the vlys. Broad weakly cyclonic flow assoc with a cool pac NW upper low moves over the state on Tuesday. This will result in a typical marine layer pattern with the morning clouds and a sunny afternoon. Max temps will be well blo normal today and Monday due to the onshore flow extensive clouds. Max temps will rebound slightly Tuesday with the higher hgts and greater sunshine but they will remain blo normal. .LONG TERM...(WED-SAT) Not much excitement for Wednesday and Thursday. The upper low moves down the Oregon coast and tilts the flow over Srn Ca into a more SW to NE orientation. There will not be much change in the weather from Tuesday on both days. Look for typical night through morning low clouds and fog pattern with max temps close to normal. The real story of the xtnd fcst is the Friday through Sunday portion. A large upper high will slowly press westward through the period hgts will rise through the period from 582 DM on Friday to 594 DM on Sunday. The onshore flow will weaken and the marine layer clouds will diminish. Max temps will rise each day. On Friday max temps will be 1 to 3 degrees above normal and by Sunday max temps will 10 to 20 degrees above normal. Next Monday looks warmer still. This could unfold into a major heat event and people should monitor the forecast for the latest developments. && .AVIATION...12/12Z... Marine layer at LAX at 11Z was 3500 feet deep. The top of the marine inversion top was at 5400 feet with a temp of 11 degs C. Skies were cloudy all the way to the coastal slopes. Cigs were at high MVFR or VFR levels in most areas, with IFR conditions confined to the foothills and slopes. Expect cigs to linger through the day in most areas, although conds will rise to VFR levels in most areas w of the mountains. Expect widespread high MVFR cigs across the region tonight. KLAX...Moderate confidence in the 12z TAF. There is a 20 percent chance that MVFR cigs will linger through 20z. There is a 20 to 30 percent chance that cigs will be in the MVFR category tonight/Mon morning. There is a 20 percent chance that se winds will rise above 10 kt through 18z this morning. KBUR...Moderate to high confidence in the 12z TAF. There is a 20 percent chance that MVFR cigs will linger through 21z. && .MARINE...12/900 AM... Small craft advisory conditions for winds are not expected through Monday morning. Northwest winds are expected to develop and increase Monday afternoon and there is a chance small craft advisory conditions will exist at times from Piedras Blancas to San Nicolas island Monday night through Friday. Northwest locally generated seas will build to around 10 feet from Piedras Blancas to San Nicolas island Tuesday and subside below 10 feet Wednesday evening. Otherwise an active storm track over the Southern Ocean last week had generated seas within 190-220 degrees relative to Ventura. The swells will build near shore through the week. Small craft advisory for hazardous sea conditions area not expected but extra currents and surging along exposed south facing shores are likely. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...Sukup/ASR AVIATION...DB MARINE...30 SYNOPSIS...Sweet weather.gov/losangeles
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
314 PM CDT SUN JUN 12 2016 .SHORT TERM...(This Evening through Monday) Issued at 308 PM CDT SUN JUN 12 2016 Currently, 20Z visible and WV imagery show a modified North Pacific Low over the Eastern Northern Plains into portions of the Upper MS Valley. A warm boundary stretches from MN to Illinois into the Ohio Valley. Meanwhile, a weak cold boundary lags behind the system through Western Nebraska into Colorado. A lee side low is positioned over southeast Colorado ahead of a minor lead shortwave. A fairly well defined upper low continues to spin over the Southern Plains. Weak lift is making its way around the low over the Southern Plains and has continued to support thunderstorms with instability of 2000 J/kg and weak shear of 20-25kts. Some of this energy may work into southern portions of the forecast area, so have added some POPs through late afternoon but don`t expect activity to persist as peak heating subsides. Out west, the previously mentioned wave will be working into the Northern portions of the Central Plains into tomorrow morning and afternoon. Have actually reduced POPs near term a bit as confidence in getting too much precip before late morning into the afternoon on Monday is not looking as good as it previously has. Weak forcing over the area with the bulk of vorticity off to the north of northeastern KS leads to lower confidence in more than slight POPs over northeast KS. Also, confidence in MCS development overnight coming in from Nebraska continues to be the main question as to whether storms hold together or if any outflow ends up over the forecast area. At this time, it looks like we could mainly be seeing any thunderstorm and showers later in the morning into the early afternoon time frame as additional lift comes from the slowly advancing cold front from western Nebraska. Not expecting severe storms at this point since lapse rates are only in the 5.5 C/km range and again shear profiles look weak. Given the expected cloud cover, have highs less than recent days mainly in the upper 80s. Expecting lows to be similar tonight with no significant air mass change taking place. .LONG TERM...(Monday Night through Sunday) Issued at 308 PM CDT SUN JUN 12 2016 Main concern for the period will be thunderstorms, some strong to severe from Monday night through Tuesday night. Monday night models continue to point toward the development of an MCS over the western high plains then moving east northeast across Nebraska and Kansas. The early morning MCS will likely have an effect on where boundaries will be located and how long clouds and any precipitation hang around. This will likely have an affect on destabilization ahead of the approaching cold front across northeast Kansas on Tuesday. Shear is sufficient as well as forecast instability for storms to be strong to severe Tuesday afternoon and Tuesday night. Main hazards look to be damaging winds and large hail. A tornado is also possible especially across east central Kansas where helicity is favorable. A relatively quiet weather period is seen from Wednesday night through Sunday. Upper level riding over the central US keeps any chances for storms very slim, although the occasional model brings slight chances during the afternoon some days. Overall, a pretty dry and hot period with temperatures topping out in the 90s. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1240 PM CDT SUN JUN 12 2016 Going with a VFR forecast right now for the terminals. It does appear that mostly subsidence will remain in control but an approaching upper wave will eventually help to saturate mid levels so forecasting mostly a mid level cloud layer overspreading the terminals by morning. Unsure on actual coverage so only going with SCT at this time. As winds calm tonight, expecting some HZ or BR at least around the KTOP/KFOE terminals. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Drake LONG TERM...Heller/53 AVIATION...Drake
Area Forecast Discussion National Weather Service Goodland KS 155 PM MDT SUN JUN 12 2016 .SHORT TERM...(This afternoon through Monday) Issued at 155 PM MDT Sun Jun 12 2016 Surface analysis indicates Cold front approximate from northern Colorado across western Nebraska with prefrontal trough extending south across eastern Colorado. Radar shows slow moving/back building thunderstorms ahead of main front in our northwest CWA, while satellite shows CU field developing into NW Kansas. This afternoon-tonight: Convection already underway is currently matching trends in RAP/HRRR along with high resolution convective allowing models (ARW/NMM). RAP analysis indicated CAP already weakening across much of our CWA with ML CIN approaching zero. Main axis of forcing is near frontal zone, and trend should be towards convection filling in across the west and spreading eastward. Initially convective environment (with high DCAPE and 10kft dry adiabatic layer) will support elevated microburst potential, and increasing CAPE associated with Tds in the 60s will support a few stronger updrafts. Shear is on the weaker end, so stronger storms will tend to be more pulsy in nature. Front will transition south, aided by possible cold pool with additional activity developing with easterly flow north of front and moderate elevated instability through the night. Mean flow 5-15kt will support slow storm motions will tend to be on the slower side. There is a anomalously moist air mass in place with PWATs already in excess of 1.5" according to RAP analysis. Strong moist inflow towards the frontal zone will lead to training and backbuilding of thunderstorms. With thunderstorm activity expected to increase in coverage and slowly spread across the region the threat for flooding warranted Flash Flood Watch issuance through tonight. Monday: Majority of guidance supports eastward trend in nighttime convective activity Monday morning with a possible lull through midday. Stronger large scale forcing associated with approaching upper level trough will support redevelopment Monday afternoon, with lull serving to prime atmosphere with increasing instability through the day. As upper low moves east stalled front will lift north with increasing veering supporting stronger shear and potential super cell development. All modes of severe weather will be possible Monday afternoon, with significant hail and some tornadoes possible. .LONG TERM...(Wednesday through Sunday) Issued at 226 AM MDT Sun Jun 12 2016 During the extended period, expect predominantly sunny skies and above normal temperatures, as an upper level ridge influence the High Plains Region. Afternoon highs will reach into the mid to upper 90s while overnight lows will range between the mid 50s to the mid 60s. The exception looks to be on Saturday, where models show a small weather disturbance moving across the area. This feature will produce slighting cooler temperatures, highs around 90, and a slight chance of showers and thunderstorms, mainly in the northeastern part of the Tri-State Area. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 1148 AM MDT Sun Jun 12 2016 VFR conditions should prevail at KGLD and KMCK through the first 6-9hr of the TAF period. Thunderstorm activity is already developing in NE Colorado (apparent on radar) and this should increase in coverage through the afternoon and spread eastward towards both KGLD and KMCK. Confidence has increased enough to fine tune mention/timing of peak thunderstorm period in the TAFs at both terminals. A few strong/severe storms will be possible, but this would mainly be in the evening/overnight, and it is still too far out to include TEMPO mention. I have less confidence in cigs/vis, as some guidance is hitting on the very good moist return late tonight and attempting to produce IFR cigs/LIFR vis after 09z through late Monday morning. These lower conditions will be dependent on thunderstorms clearing, and there is still an indication that thunderstorms may linger near both terminals after 09z. Due to the low confidence I kept CIGS 3000kft or higher and vis 6sm or higher. This will need to be monitored. && .GLD Watches/Warnings/Advisories... KS...Flash Flood Watch through late tonight for KSZ001>003-013>015- 027>029-041-042. CO...Flash Flood Watch through late tonight for COZ090>092. NE...Flash Flood Watch through late tonight for NEZ079>081. && $$ SHORT TERM...DR LONG TERM...BW AVIATION...DR