Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/22/16

Area Forecast Discussion
National Weather Service Tucson AZ
856 PM MST THU JUL 21 2016

.SYNOPSIS...Hotter and drier conditions are expected Friday into
Sunday with some record high temperatures likely to fall. There will
be just enough moisture around for a few storms near the Mexico and
New Mexico border each of those afternoons. Then moisture will
increase across much of the area early next week for an increase in
storms and somewhat cooler afternoon temperatures.

&&

.DISCUSSION...Satellite and radar trends show lingering showers and
thunderstorms continuing to move in from the east across parts of
Greenlee, Graham and Cochise counties as they move to the west
northwest. A few lingering showers and storms also over parts of the
Tohono O`Odham nation, not to mention some isolated activity south
of the border. We should see a gradual decrease in shower and
thunderstorm coverage through the remainder of the night. Made some
minor tweaks to the POP grids to reflect these recent trends.

As of 03Z (8 PM MST), temperatures across the region ranged from the
upper 70s to the upper 90s, with the Tucson International Airport
reporting a temp of 94 degs, after achieving an afternoon high of
107 degs, which was 8 degs above normal for this date. The inherited
overnight low temperature forecasts seem to be fine, but will make
some adjustments to the short term hourly temperature grids to
reflect the most recent trends.

For details beyond tonight, please refer to the previous discussion
below.

&&

.AVIATION...VALID THRU 23/06.
Isolated showers and thunderstorms will continue mainly along the
border with New Mexico and also along the immediate border with
Mexico as a complex over Sonora helps to keep isolated convection
going mainly south of the border tonight, but can`t rule out
outflows triggering additional isolated showers and/or storms into
the early morning hours. Ceilings generally above 12K FT, although
lower ceilings expected near thunderstorms. Expect slightly lesser
showers and thunderstorms on Friday afternoon and early evening as
drier air from the east continues to push west. Winds generally
light with typical diurnal trends, except near thunderstorms where
winds will be variable and gusty. Aviation discussion not updated
for TAF amendments.

&&

.FIRE WEATHER...Daily rounds of showers/thunderstorms will
linger into the weekend with coverage waning Saturday and Sunday.
A greater chance of storms will move into the area early next week.
Outside of gusty thunderstorm outflows, 20-foot winds will be
terrain driven and mostly less than 15 mph.

&&

.PREV DISCUSSION...Friday and Saturday drier air invades the
region which is currently on our door step looking at the water
vapor loop. The overall result of this will be a reduction in the
convection and resultant cloud cover with much of it being limited
to our eastern and southern border areas. The other affect of this
will be to allow afternoon temperatures to increase the next few
days peaking Friday and Saturday afternoons about 10 degrees above
average and at or slightly above records for several locations. I
tweaked pops down a bit a few areas and added a degree to the high
temperature to many areas on Saturday.

On Sunday lower level thickness values begin to drop back with
moisture beginning to increase from the south. This is basically
beginning to occur thanks to a nudge from the tropics but at this
time believe the main push of moisture will be Sunday night into
Monday. So for now only made minor adjustments to the pops Sunday
and went with about 5 degrees of cooling for the afternoon when
compared to Saturday.

For Monday onward, nudged pops upward with the current trend in the
models and introduced chance of storms to the western deserts
throughout the week. May need to adjust them up further early in the
week but will wait a bit and see how this begins to unfold. I also
nudged afternoon high temperatures down a couple of degrees but
there is potential to nudge them down further one or two of those
days depending on the moisture surge. Still have a decent amount of
discrepancy in the lower level thickness forecast in the models with
the ECMWF being on the cooler side.

.TWC Watches/Warnings/Advisories...None.

&&

$$

DISCUSSION...Mollere
PREVIOUS DISCUSSION...Cerniglia
AVIATION/FIRE WEATHER....Cantin

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson



  [top] Area Forecast Discussion National Weather Service Flagstaff AZ 338 PM MST THU JUL 21 2016 .SYNOPSIS...Scattered showers and storms are expected again Friday afternoon across much of northern Arizona. Storm coverage will decrease significantly this weekend as drier air moves in from the west. Moisture and storm chances could increase again next week, especially along and south of the Mogollon Rim. && .DISCUSSION...Scattered showers and storms are ongoing late this afternoon across northern Arizona. The overall intensity is much weaker than what we have seen the last couple of days. Storm coverage will decrease after sunset, with some showers and storms lingering into the overnight hours. Scattered storms are expected again Friday afternoon. Instability should be a little greater, so the overall intensity of the storms may be stronger than what we have seen today. Storms will be moving more to the east as opposed to the north like we have seen the past few days. The main threat with any storm will be heavy rain,. Saturday and Sunday...Drier air moves in from the west, greatly reducing storm chances across Yavapai and Coconino Counties. Southern Navajo and Apache Counties will see the greatest chance of continuing thunderstorms. Next week...Models continue to show the ridge lifting back to the north early next week, which would allow for moisture to make its way back into northern Arizona. If this happens, thunderstorm chances would become more widespread, especially from the Mogollon Rim south. && .AVIATION...For the 00Z package...Expect isolated to scattered showers and thunderstorms until sunset then diminishing to a slight chance overnight. On Friday...Look for another round of isolated to scattered showers and storms. Conditions will remain primarily VFR but local MVFR in heavy rain is possible in stronger storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...On Friday and Saturday...a drier westerly flow will begin a downward trend in thunderstorm activity over much of the area. The exception...scattered storm activity will continue over the region of the White Mountains. Sunday through Tuesday...Expect lower thunderstorm chances and decreased afternoon humidity on Sunday. Moisture and the chance for storms may increase on Monday and Tuesday from the Mogollon Rim south. && .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 Phoenix AZ 146 PM MST THU JUL 21 2016 .SYNOPSIS... The dry weather across southeast California and southwest Arizona will begin to spread eastward, with the chances for showers and thunderstorms gradually dwindling across central Arizona the next several days. The combination of thinning moisture and a much warmer atmosphere building into the region, will cause afternoon temperatures to soar, especially Friday and Saturday. Temperatures will cool a bit Sunday, but still remain fairly hot into next week, as thunderstorm chances return to the forecast. && .DISCUSSION... Latest satellite imagery shows agitated CU developing across the higher peaks of Arizona with the strongest storms across the White Mountains and the Mogollon Rim. Some recent AMDAR flights out of KPHX show that the mid-level flow continues to veer to the southwest, which explains the general cloud movement to the north and northeast in central Arizona. Meanwhile, no well-defined vort maxes or inverted troughs were evident on WV imagery. Conceptually speaking, conditions remain unfavorable for organized convection in the lower deserts for late this afternoon and this evening. However, with PWATs around 1.4 inches, conditions remain sufficiently moist for scattered activity across the higher terrain east of Phoenix. Latest convective allowing guidance continues to suggest that showers and thunderstorms will develop across Pinal County late this afternoon. Model consensus indicates that propagation into Maricopa County is unlikely. However, an outflow boundary is expected to move through the Phoenix area this evening along with the possibility of blowing dust. SPC SSEO continues to suggest that strong storms are not anticipated in the lower deserts, though depiction in the hi-res guidance points to the possibility of mid-level debris along with isolated sprinkles/light showers. Otherwise, focus will be on the warming trend the next few days. Latest NAEFS percentiles exceed the 90th percentile across southeastern California by Friday and look to approach the 98th percentile across the Imperial Valley by Saturday. Much of Imperial County was upgraded to an Excessive Heat Warning. The Warning continues for the Phoenix area. Elsewhere, anomalies are not as extreme and the Watch was cancelled. && .PREVIOUS DISCUSSION... We`ll start off with the main weather concern over the next seven days which is a relatively short period of excessive heat. The sprawling central CONUS 500 mb anti-cyclone will migrate toward the Southwest States today and hover over us on Friday and Saturday. This will help quell chances for showers/thunderstorms while temperatures show a marked upward jump. Temperatures at 850 mb will hover around 32-33C both days, which will put lower desert locations firmly in the 110-115F range. Model range continues to tighten on this solution and don`t see a lot of wiggling likely as the event arrives. Climatologically-driven Excessive Heat Warning criteria is being met in the Phoenix Metro Area both days and in northwest Pinal County communities. Therefore, upgraded the watch to a warning given our higher confidence. Of concern will also be the overnight low temperatures, likely not falling below 90 in the urban areas. By Sunday, the PacNW trough we`ve been watching in the models for several days remains in the forecast and is expected to suppress the ridge overhead, resulting in a noted cool-down in the forecast (though it will still be fairly hot, just not excessively so). As for convection, we continue to be on a downward trend today through Saturday. Boundary layer mixing ratios this afternoon across most of southern Arizona will barely be above 8 g/kg, which is a good approximation of enough moisture to translate into positive CAPE values. We expect to see more shower/storms in the area but coverage will likely not be impressive. With a deep and well-mixed boundary layer, outflows will continue to remain a threat along with the blowing dust they bring. For Friday and Saturday, moisture and instability values fall further along with precipitation chances. Once we get past the hottest days of Friday and Saturday, the upper level (250 mb) flow pattern will re-adjust. It still appears that the mid-level anti-cyclone will take-up a position just to the north of Arizona, which will allow deep easterly flow to stretch up the Rio Grande Valley and across southern New Mexico/Arizona/California. Boundary layer mixing ratio values climb back into the 9-10 g/kg range by Monday and remain there through the week. This pattern open the door for more instability to develop, the transversing of easterly waves, and favorable propagation vectors to promote storm movement off the mountains and into the lower deserts. This pattern could remain in place through the end of the month. && .AVIATION... South-Central Arizona Including KPHX, KIWA, and KSDL: Thin high level cirrus will carry through the afternoon with mid- level CU/CB development popping over the typically favored mountains well N, E and SE of the Phoenix-area terminals. Midday winds to be on the lighter side with VRB headings before settling into westerly directions between 20z-22z. Regionally, moisture is be thinning and flow aloft is turning less favorable for desert storms so chances of storms surviving into the Phoenix-metro are low. However, several hi-res models and observed forecast soundings indicate potential for outflow driven wind shifts likely from the southeast (anywhere between 140-170 or so) on the headings post 22/02z for an initial estimate. Will be able to better time the shifts once storm development between Casa Grande and Tucson begins in the afternoon. Debris cloudiness with some very light showers/virga could follow in the wake of the outflow, with VCSH coverage included generally post 22/04z for the terminals for just a few hours. Southeast California/Southwest Arizona including KIPL and KBLH: No aviation concerns at the TAF site next 24 hours as thunderstorm activity will remain well off to the east and to the east of the lower Colorado River valley. Winds to favor the south next 24 hours at KBLH with a few afternoon gusts over 18kt possible. Winds to favor the west at KIPL turning for a spell to the southeast mainly during the afternoon hours today. Aviation Discussion not updated for amended TAFs. && .FIRE WEATHER... Saturday through Wednesday...Temperatures are climbing to well above normal territory through the weekend as moisture levels thin and humidity values drop. Chances for thunderstorms/wetting rain dwindle and become almost limited to the higher terrain of eastern Arizona by Saturday. Consequently, afternoon humidity levels will fall below 15 percent over the weekend before increasing to the 15-20 percent range beginning Sunday and into next week as thunderstorm chances slowly increase from east to west. Higher humidity values can be expected in the higher terrain locations. High temperatures will taper off next week as humidity levels climb but will stay near or slightly above seasonal normals. Outside of thunderstorms, winds will be typical with some afternoon gustiness. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Excessive Heat Warning from midnight tonight to midnight MST Saturday night for AZZ023-028. CA...Excessive Heat Warning from midnight tonight to midnight PDT Saturday night for CAZ033. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hirsch PREVIOUS DISCUSSION...Iniguez AVIATION...Nolte/CB FIRE WEATHER...Deemer/CB
Area Forecast Discussion National Weather Service Tucson AZ 1244 PM MST THU JUL 21 2016 .SYNOPSIS...Hotter and drier conditions are expected Friday into Sunday with some record high temperatures likely to fall. There will be just enough moisture around for a few storms near the Mexico and New Mexico border each of those afternoons. Then moisture will increase across much of the area early next week for an increase in storms and somewhat cooler afternoon temperatures. && .DISCUSSION...Convection kicking off across the higher terrain early this afternoon with individual cells drifting to the NNW. The convection will continue to develop and expand in coverage through the afternoon with locally gusty winds with some blowing dust being the biggest concern. There will be some decent rainers but with slowly diminishing PWs less of a threat outside of training echoes. All this activity will die off this evening much like yesterday as there isn`t any larger scale forcing to keep things going. Then Friday and Saturday drier air invades the region which is currently on our door step looking at the water vapor loop. The overall result of this will be a reduction in the convection and resultant cloud cover with much of it being limited to our eastern and southern border areas. The other affect of this will be to allow afternoon temperatures to increase the next few days peaking Friday and Saturday afternoons about 10 degrees above average and at or slightly above records for several locations. I tweaked pops down a bit a few areas and added a degree to the high temperature to many areas on Saturday. On Sunday lower level thickness values begin to drop back with moisture beginning to increase from the south. This is basically beginning to occur thanks to a nudge from the tropics but at this time believe the main push of moisture will be Sunday night into Monday. So for now only made minor adjustments to the pops Sunday and went with about 5 degrees of cooling for the afternoon when compared to Saturday. For Monday onward nudged pops upward with the current trend in the models and introduced chance of storms to the western deserts throughout the week. May need to adjust them up further early in the week but will wait a bit and see how this begins to unfold. I also nudged afternoon high temperatures down a couple of degrees but there is potential to nudge them down further one or two of those days depending on the moisture surge. Still have a decent amount of discrepancy in the lower level thickness forecast in the models with the ECMWF being on the cooler side. && .AVIATION...VALID THRU 23/00. Scattered showers and thunderstorms will develop through at least 03Z with impacts to terminals including gusty winds, heavy rainfall, and the potential for reductions in visibility. In general VFR conditions will be prevalent throughout, unless a storm develops directly over the airport. Cloud bases will hover around 8 or 9 thousand feet. Storm chances will drop quickly after 03Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Daily rounds of showers/thunderstorms will linger into the weekend with coverage waning Saturday and Sunday. A greater chance of storms will move into the area early next week. Outside of gusty thunderstorm outflows, 20-foot winds will be terrain driven and mostly less than 15 mph. && .TWC Watches/Warnings/Advisories... None. && $$ PUBLIC...CERNIGLIA AVIATION....CANTIN FIRE WEATHER...CANTIN Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion National Weather Service Phoenix AZ 1109 AM MST THU JUL 21 2016 .UPDATE...To Aviation Discussion... && .SYNOPSIS... The dry weather across southeast California and southwest Arizona will begin to spread eastward, with the chances for showers and thunderstorms gradually dwindling across central Arizona the next several days. The combination of thinning moisture and a much warmer atmosphere building into the region, will cause afternoon temperatures to soar, especially Friday and Saturday. Temperatures will cool a bit Sunday, but still remain fairly hot into next week, as thunderstorm chances return to the forecast. && .DISCUSSION... Latest morning Phoenix sounding shows that winds in the 700-500 mb layer have weakened and veered to southerly around the anticyclone in the southern Plains. Conceptually speaking, this pattern is less favorable for convection in the lower deserts. Latest convective- allowing model guidance corroborates this, depicting afternoon development mainly across eastern Arizona and the higher terrain of east of Phoenix. Nevertheless, sufficient moisture is present to trigger isolated activity, particularly across Pinal County this afternoon. SSEO suggests intense cells are not probable. Other thunderstorm impacts such as wind and dust are certainly more likely in these areas. Minor adjustments were made to the short-term temperatures. Otherwise, the forecast remains on track with well- above normal temperatures expected. && .PREVIOUS DISCUSSION... We`ll start off with the main weather concern over the next seven days which is a relatively short period of excessive heat. The sprawling central CONUS 500 mb anti-cyclone will migrate toward the Southwest States today and hover over us on Friday and Saturday. This will help quell chances for showers/thunderstorms while temperatures show a marked upward jump. Temperatures at 850 mb will hover around 32-33C both days, which will put lower desert locations firmly in the 110-115F range. Model range continues to tighten on this solution and don`t see a lot of wiggling likely as the event arrives. Climatologically-driven Excessive Heat Warning criteria is being met in the Phoenix Metro Area both days and in northwest Pinal County communities. Therefore, upgraded the watch to a warning given our higher confidence. Of concern will also be the overnight low temperatures, likely not falling below 90 in the urban areas. Further to the west, while temperatures will be just as warm, climate in those locations is also warm thus temperatures not as anomalous. In addition, overnight low temperatures will be several degrees cooler. Given that confidence remains lower of hitting excessive heat thresholds, decided to maintain the watch. Next shift will likely need to make a final go/no-go decision. By Sunday, the PacNW trough we`ve been watching in the models for several days remains in the forecast and is expected to suppress the ridge overhead, resulting in a noted cool-down in the forecast (though it will still be fairly hot, just not excessively so). As for convection, we continue to be on a downward trend today through Saturday. Boundary layer mixing ratios this afternoon across most of southern Arizona will barely be above 8 g/kg, which is a good approximation of enough moisture to translate into positive CAPE values. We expect to see more shower/storms in the area but coverage will likely not be impressive. With a deep and well-mixed boundary layer, outflows will continue to remain a threat along with the blowing dust they bring. For Friday and Saturday, moisture and instability values fall further along with precipitation chances. Once we get past the hottest days of Friday and Saturday, the upper level (250 mb) flow pattern will re-adjust. It still appears that the mid-level anti-cyclone will take-up a position just to the north of Arizona, which will allow deep easterly flow to stretch up the Rio Grande Valley and across southern New Mexico/Arizona/California. Boundary layer mixing ratio values climb back into the 9-10 g/kg range by Monday and remain there through the week. This pattern open the door for more instability to develop, the transversing of easterly waves, and favorable propagation vectors to promote storm movement off the mountains and into the lower deserts. This pattern could remain in place through the end of the month. && .AVIATION... South-Central Arizona Including KPHX, KIWA, and KSDL: Thin high level cirrus will carry through the afternoon with mid- level CU/CB development popping over the typically favored mountains well N, E and SE of the Phoenix-area terminals. Midday winds to be on the lighter side with VRB headings before settling into westerly directions between 20z-22z. Regionally, moisture is be thinning and flow aloft is turning less favorable for desert storms so chances of storms surviving into the Phoenix-metro are low. However, several hi-res models and observed forecast soundings indicate potential for outflow driven wind shifts likely from the southeast (anywhere between 140-170 or so) on the headings post 22/02z for an initial estimate. Will be able to better time the shifts once storm development between Casa Grande and Tucson begins in the afternoon. Debris cloudiness with some very light showers/virga could follow in the wake of the outflow, with VCSH coverage included generally post 22/04z for the terminals for just a few hours. Southeast California/Southwest Arizona including KIPL and KBLH: No aviation concerns at the TAF site next 24 hours as thunderstorm activity will remain well off to the east and to the east of the lower Colorado River valley. Winds to favor the south next 24 hours at KBLH with a few afternoon gusts over 18kt possible. Winds to favor the west at KIPL turning for a spell to the southeast mainly during the afternoon hours today. Aviation Discussion not updated for amended TAFs. && .FIRE WEATHER... Saturday through Wednesday...Temperatures are climbing to well above normal territory through the weekend as moisture levels thin and humidity values drop. Chances for thunderstorms/wetting rain dwindle and become almost limited to the higher terrain of eastern Arizona by Saturday. Consequently, afternoon humidity levels will fall below 15 percent over the weekend before increasing to the 15-20 percent range beginning Sunday and into next week as thunderstorm chances slowly increase from east to west. Higher humidity values can be expected in the higher terrain locations. High temperatures will taper off next week as humidity levels climb but will stay near or slightly above seasonal normals. Outside of thunderstorms, winds will be typical with some afternoon gustiness. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Excessive Heat Warning from midnight tonight to midnight MST Saturday night for AZZ023-028. CA...Excessive Heat Warning from midnight tonight to midnight PDT Saturday night for CAZ033. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hirsch PREVIOUS DISCUSSION...Iniguez AVIATION...Nolte/CB FIRE WEATHER...Deemer/CB
Area Forecast Discussion National Weather Service Phoenix AZ 1109 AM MST THU JUL 21 2016 .UPDATE...To Aviation Discussion... && .SYNOPSIS... The dry weather across southeast California and southwest Arizona will begin to spread eastward, with the chances for showers and thunderstorms gradually dwindling across central Arizona the next several days. The combination of thinning moisture and a much warmer atmosphere building into the region, will cause afternoon temperatures to soar, especially Friday and Saturday. Temperatures will cool a bit Sunday, but still remain fairly hot into next week, as thunderstorm chances return to the forecast. && .DISCUSSION... Latest morning Phoenix sounding shows that winds in the 700-500 mb layer have weakened and veered to southerly around the anticyclone in the southern Plains. Conceptually speaking, this pattern is less favorable for convection in the lower deserts. Latest convective- allowing model guidance corroborates this, depicting afternoon development mainly across eastern Arizona and the higher terrain of east of Phoenix. Nevertheless, sufficient moisture is present to trigger isolated activity, particularly across Pinal County this afternoon. SSEO suggests intense cells are not probable. Other thunderstorm impacts such as wind and dust are certainly more likely in these areas. Minor adjustments were made to the short-term temperatures. Otherwise, the forecast remains on track with well- above normal temperatures expected. && .PREVIOUS DISCUSSION... We`ll start off with the main weather concern over the next seven days which is a relatively short period of excessive heat. The sprawling central CONUS 500 mb anti-cyclone will migrate toward the Southwest States today and hover over us on Friday and Saturday. This will help quell chances for showers/thunderstorms while temperatures show a marked upward jump. Temperatures at 850 mb will hover around 32-33C both days, which will put lower desert locations firmly in the 110-115F range. Model range continues to tighten on this solution and don`t see a lot of wiggling likely as the event arrives. Climatologically-driven Excessive Heat Warning criteria is being met in the Phoenix Metro Area both days and in northwest Pinal County communities. Therefore, upgraded the watch to a warning given our higher confidence. Of concern will also be the overnight low temperatures, likely not falling below 90 in the urban areas. Further to the west, while temperatures will be just as warm, climate in those locations is also warm thus temperatures not as anomalous. In addition, overnight low temperatures will be several degrees cooler. Given that confidence remains lower of hitting excessive heat thresholds, decided to maintain the watch. Next shift will likely need to make a final go/no-go decision. By Sunday, the PacNW trough we`ve been watching in the models for several days remains in the forecast and is expected to suppress the ridge overhead, resulting in a noted cool-down in the forecast (though it will still be fairly hot, just not excessively so). As for convection, we continue to be on a downward trend today through Saturday. Boundary layer mixing ratios this afternoon across most of southern Arizona will barely be above 8 g/kg, which is a good approximation of enough moisture to translate into positive CAPE values. We expect to see more shower/storms in the area but coverage will likely not be impressive. With a deep and well-mixed boundary layer, outflows will continue to remain a threat along with the blowing dust they bring. For Friday and Saturday, moisture and instability values fall further along with precipitation chances. Once we get past the hottest days of Friday and Saturday, the upper level (250 mb) flow pattern will re-adjust. It still appears that the mid-level anti-cyclone will take-up a position just to the north of Arizona, which will allow deep easterly flow to stretch up the Rio Grande Valley and across southern New Mexico/Arizona/California. Boundary layer mixing ratio values climb back into the 9-10 g/kg range by Monday and remain there through the week. This pattern open the door for more instability to develop, the transversing of easterly waves, and favorable propagation vectors to promote storm movement off the mountains and into the lower deserts. This pattern could remain in place through the end of the month. && .AVIATION... South-Central Arizona Including KPHX, KIWA, and KSDL: Thin high level cirrus will carry through the afternoon with mid- level CU/CB development popping over the typically favored mountains well N, E and SE of the Phoenix-area terminals. Midday winds to be on the lighter side with VRB headings before settling into westerly directions between 20z-22z. Regionally, moisture is be thinning and flow aloft is turning less favorable for desert storms so chances of storms surviving into the Phoenix-metro are low. However, several hi-res models and observed forecast soundings indicate potential for outflow driven wind shifts likely from the southeast (anywhere between 140-170 or so) on the headings post 22/02z for an initial estimate. Will be able to better time the shifts once storm development between Casa Grande and Tucson begins in the afternoon. Debris cloudiness with some very light showers/virga could follow in the wake of the outflow, with VCSH coverage included generally post 22/04z for the terminals for just a few hours. Southeast California/Southwest Arizona including KIPL and KBLH: No aviation concerns at the TAF site next 24 hours as thunderstorm activity will remain well off to the east and to the east of the lower Colorado River valley. Winds to favor the south next 24 hours at KBLH with a few afternoon gusts over 18kt possible. Winds to favor the west at KIPL turning for a spell to the southeast mainly during the afternoon hours today. Aviation Discussion not updated for amended TAFs. && .FIRE WEATHER... Saturday through Wednesday...Temperatures are climbing to well above normal territory through the weekend as moisture levels thin and humidity values drop. Chances for thunderstorms/wetting rain dwindle and become almost limited to the higher terrain of eastern Arizona by Saturday. Consequently, afternoon humidity levels will fall below 15 percent over the weekend before increasing to the 15-20 percent range beginning Sunday and into next week as thunderstorm chances slowly increase from east to west. Higher humidity values can be expected in the higher terrain locations. High temperatures will taper off next week as humidity levels climb but will stay near or slightly above seasonal normals. Outside of thunderstorms, winds will be typical with some afternoon gustiness. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Excessive Heat Warning from midnight tonight to midnight MST Saturday night for AZZ023-028. CA...Excessive Heat Warning from midnight tonight to midnight PDT Saturday night for CAZ033. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...Hirsch PREVIOUS DISCUSSION...Iniguez AVIATION...Nolte/CB FIRE WEATHER...Deemer/CB
Area Forecast Discussion National Weather Service Flagstaff AZ 918 AM MST THU JUL 21 2016 .SYNOPSIS...Another round of showers and thunderstorms is expected from late this morning through early evening. Drier westerly flow will decrease shower and thunderstorm coverage across western Arizona Friday into the weekend, though decent chances for thunderstorms will remain across southern Navajo and Apache counties. Moisture and storm chances could increase again next week, especially along and south of the Mogollon Rim. && .UPDATE...Today will be another day of widespread showers and thunderstorms across northern Arizona. The main threats with these storms will be very heavy rain, which could lead to localized flash flooding. The previous forecast is in good shape and no changes were made. && .PREV DISCUSSION /342 AM MST/...Another round of showers and thunderstorms is expected across all of northern Arizona today, beginning after 10 AM MST. Storms will initially develop in the higher terrain and slowly work their way to the lower elevations. The main threat with storms will once again be localized very heavy rain due to the slow storm movement, which could lead to localized flash flooding. The stronger storms will also be capable of producing small hail and gusty winds. Beginning Friday, the axis of strong high pressure will shift over or just south of the forecast area and drier air will start to move in from the west. This will reduce storm chances across Coconino and Yavapai Counties into the weekend. The greatest storm chances will remain over southern Navajo and Apache Counties where the highest moisture will linger. Most model guidance shows the ridge shifting back northward possibly as early as Sunday but more likely Monday into midweek. This would allow for some better moisture and storm chances to return, especially for areas along and south of the Mogollon Rim and White Mountains. Depending on where the high eventually sets up, we could see some east or northeast steering flow off the higher terrain which is favorable for some stronger storms in the late afternoon and evening in Gila County and the lower elevations of Yavapai County. Far northern Arizona (along/north of Grand Canyon to Window Rock) often remains drier in this pattern. With high pressure in place, expect hot temperatures in this area, 110+ at Phantom Ranch, 102-104 at Page and near 90 at Grand Canyon south rim. && .AVIATION...For the 18Z package...Expect scattered to numerous showers and thunderstorms. Conditions will remain primarily VFR but local MVFR in heavy rain is possible in stronger storms. Activity should decrease after sunset. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A wet monsoon pattern will remain in place today resulting in scattered thunderstorms with locally heavy rain possible. By Friday, a drier westerly flow will begin a downward trend in thunderstorm activity. Saturday through Monday...Expect lower thunderstorm chances and decreased afternoon humidity over the weekend. Moisture may increase on Monday from the Mogollon Rim south. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...Mottice/JJ AVIATION...AT FIRE WEATHER...MCS For Northern Arizona weather information visit weather.gov/flagstaff
Area Forecast Discussion National Weather Service Tucson AZ 845 AM MST THU JUL 21 2016 .SYNOPSIS...A decrease in thunderstorms activity will occur over the next several days as the air mass over the region dries out. As a result temperatures will climb to roughly 10 degrees warmer than average Friday and Saturday with record high temperatures possible both days. Monsoon moisture will then gradually return Sunday onward for an overall increase in convection and a slight cooling of afternoon temperatures. && .DISCUSSION...Drying has not started yet in any significant fashion thus we still have nearly 1.5" PW on the morning sounding with a little less to the east. Also the sounding has a slightly better thermal profile compared to yesterday with a touch of cooling aloft an warming below. The upshot, the atmosphere is ready with plenty of sunshine to help out. Not much if anything noticeable out there to help focus or provide extra lift so this will primarily be another diurnal, terrain driven day much like yesterday. The latest runs of the HRRR and UA WRF NAM agree so would expect convection to begin to develop 18-19z over the higher terrain to the south and southeast then move to the NNW through the day, much like yesterday. More noticeable drying to take place from the east tomorrow and Saturday and that is apparent on this mornings water vapor imagery. This should provide for a reduction in the convection across the area while also lifting afternoon temperatures to roughly 10 degrees warmer than average, which means hot but not quite heat advisory hot. That said we will likely see a few record highs fall over the next few days. The moisture will begin to return to the region later Sunday into next week which will enhance the convection threat and put us back into a somewhat active pattern once again. Thankfully the extra clouds and scattered showers will trim a few degrees of the high temperatures next week. Cerniglia && .AVIATION...VALID THRU 22/18. Sct-bkn clouds at 6-9k ft agl and bkn-ovc clouds at 10-15k ft agl developing with isolated to scattered showers and T-storms today into this evening. Once again, heavy rainfall, gusty winds, and some areas of blowing dust will be the biggest concerns. The showers and storms will diminish aft 22/04Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Moisture in place will lead to the showers and thunderstorms again today, developing after 11 am over higher terrain and drifting to the north. A drying trend will then lead to reduced coverage of showers and thunderstorms Friday into this weekend. Moisture will increase again early next week resulting in an uptick in convection. Outside of gusty thunderstorm outflows, 20- foot winds will be terrain driven and mostly less than 15 mph. && .CLIMATE...Record high temperatures will be approached at a few spots today then most of the area will be at or near record highs Friday and Saturday. && .TWC Watches/Warnings/Advisories...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1223 PM CDT WED JUL 20 2016 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 251 AM CDT WED JUL 20 2016 A warm night tonight with temperatures still near 80 in many locations. A little more southerly wind in past days likely keeping the boundary layer more more mixed than previous nights. Convection tonight is also farther north and west, leaving the forecast area under mostly clear skies at this hour. Temperatures rise a degree or two from yesterdays numbers, with highs in the middle 90s to near 100. Heat indicies running from 100-109F across the area as the excessive heat warning continues. A little more wind today but not likely to make it feel much cooler. Lows tonight fall into the middle 70s to near 80. .LONG TERM...(Thursday through Tuesday) Issued at 251 AM CDT WED JUL 20 2016 Only minor changes to previous forecast. Upper high still in place into the late week before weakening late Friday into the weekend. Southwest low level flow and general subsidence keep the hot conditions in place with little opportunity for precipitation. 850mb temps continue their rise into Thursday and remain fairly steady into Saturday with the main challenges being in the specifics of the air and wet bulb temps. Went on the warmer and drier side of guidance given model performance in recent similar environments. Heat index values still looking to reach 103 to 110 through Saturday. Upper wave passing over the northern states still looks to drag a cold front into the area Saturday night into Sunday for at least cooler temps and some chance for precipitation. Chances should linger into Tuesday as another wave takes a similar track to the north, with isentropic lift resulting. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1223 PM CDT WED JUL 20 2016 VFR conditions are expected through the period. LLWS criteria still looks best in central Kansas and have continued to leave this mention out of the TAFs. && .TOP Watches/Warnings/Advisories... Excessive Heat Warning until 7 PM CDT Saturday for KSZ008>012- 020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...67 LONG TERM...65 AVIATION...Heller
Area Forecast Discussion National Weather Service Goodland KS 1119 AM MDT WED JUL 20 2016 .SHORT TERM...(Today and tonight) Issued at 300 AM MDT Wed Jul 20 2016 Short term concerns are hot temperatures over the next few days with heat index maximums near 105 and heat index minimums around 75 with the possibility of thunderstorms each day. The large high pressure area aloft over the central United States flattens somewhat through the end of the week and retrogrades back over the southwest as a couple of short wave troughs lift out of the southwest and track up the back side of the ridge and a larger upper trough tracks through the northwest U.S. along the Canadian border. The upper trough emerges east of the Rockies Friday night over southern Saskatchewan and eastern Montana. A persistent surface trough remains generally in place over the western portion of the forecast area through Friday with mainly south winds across the region ahead of the trough. As the upper ridge flattens over the central U.S. and the upper trough moves east of the northern Rockies by late Friday and over the northern plains by Friday night, a cold front is expected to begin moving into the central high plains region. Temperatures across the forecast area will remain hot ahead of this front with highs well in the 90s to lower 100s and lows in the 60s to middle 70s. Combined with dewpoints that remain mostly in the lower 60s across the northern and eastern extent of the forecast area, expect maximum heat index values near 105 with minimum heat index values in the middle 70s across the same area. The heat advisory remains in effect for those areas and looks to be on track, so will leave it as is. With short wave impulses moving east of the Rockies and across the plains each day with moisture convergence and increased instabilty in the vicinity of the surface trough over the western sections of the forecast area, expect isolated to scattered thunderstorms developing west of the forecast area each afternoon and evening to move eastward through the evening and overnight hours with storms dissipating as they move further east into the ridge. .LONG TERM...(Saturday through Tuesday) Issued at 233 AM MDT Wed Jul 20 2016 Ridge breaks down and slides westward as we head into Saturday and Sunday. A nearly stationary theta-e boundary associated with a cold front will be in place from southwest to northeast across the CWA on Saturday and will strengthen as we head into Sunday, allowing for slgt chc to chc PoPs across the area mainly during the mid afternoon through late evening. Surface low pressure will remain in place in the vicinity of this boundary due to lee side upper level divergent flow. CAPE values are expected to be up to 1600 J/Kg and shear will be very low thus severe potential will be limited to gusty winds and perhaps large hail in the presence of DCAPE values around 700 to 1200 J/Kg. Much cooler temperatures much closer to seasonal averages will prevail in the wake of this cold front. Troughing will take shape over the eastern US as we head into Monday. A cold front will push southward at this time and back into the CWA on Monday afternoon, giving us another chance of thunderstorms through the day and into the evening. There is some disagreement with the placement of the front however; both global models indicate the same general timing of the feature. The front will wash out as we head into Tuesday and a ridge will begin to build over the western states. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1119 AM MDT Wed Jul 20 2016 VFR conditions will continue through the TAF period at both KGLD and KMCK terminals. Thunderstorm activity may develop along a surface trough in eastern colorado and move into northwest Kansas and southwest Nebraska. Confidence was too low to include mention in either KGLD or KMCK TAF as coverage may remain very isolated. Winds should remain less than 12kt through the TAF period, though a LLJ developing tonight may lead to low level wind shear developing at both terminals. Confidence was higher in wind shear at KMCK, so I left mention out of KGLD for now. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory until 7 PM CDT Friday for KSZ002>004-014>016-028- 029. CO...NONE. NE...Heat Advisory until 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...LOCKHART LONG TERM...TL AVIATION...DR
Area Forecast Discussion National Weather Service Goodland KS 1119 AM MDT WED JUL 20 2016 .SHORT TERM...(Today and tonight) Issued at 300 AM MDT Wed Jul 20 2016 Short term concerns are hot temperatures over the next few days with heat index maximums near 105 and heat index minimums around 75 with the possibility of thunderstorms each day. The large high pressure area aloft over the central United States flattens somewhat through the end of the week and retrogrades back over the southwest as a couple of short wave troughs lift out of the southwest and track up the back side of the ridge and a larger upper trough tracks through the northwest U.S. along the Canadian border. The upper trough emerges east of the Rockies Friday night over southern Saskatchewan and eastern Montana. A persistent surface trough remains generally in place over the western portion of the forecast area through Friday with mainly south winds across the region ahead of the trough. As the upper ridge flattens over the central U.S. and the upper trough moves east of the northern Rockies by late Friday and over the northern plains by Friday night, a cold front is expected to begin moving into the central high plains region. Temperatures across the forecast area will remain hot ahead of this front with highs well in the 90s to lower 100s and lows in the 60s to middle 70s. Combined with dewpoints that remain mostly in the lower 60s across the northern and eastern extent of the forecast area, expect maximum heat index values near 105 with minimum heat index values in the middle 70s across the same area. The heat advisory remains in effect for those areas and looks to be on track, so will leave it as is. With short wave impulses moving east of the Rockies and across the plains each day with moisture convergence and increased instabilty in the vicinity of the surface trough over the western sections of the forecast area, expect isolated to scattered thunderstorms developing west of the forecast area each afternoon and evening to move eastward through the evening and overnight hours with storms dissipating as they move further east into the ridge. .LONG TERM...(Saturday through Tuesday) Issued at 233 AM MDT Wed Jul 20 2016 Ridge breaks down and slides westward as we head into Saturday and Sunday. A nearly stationary theta-e boundary associated with a cold front will be in place from southwest to northeast across the CWA on Saturday and will strengthen as we head into Sunday, allowing for slgt chc to chc PoPs across the area mainly during the mid afternoon through late evening. Surface low pressure will remain in place in the vicinity of this boundary due to lee side upper level divergent flow. CAPE values are expected to be up to 1600 J/Kg and shear will be very low thus severe potential will be limited to gusty winds and perhaps large hail in the presence of DCAPE values around 700 to 1200 J/Kg. Much cooler temperatures much closer to seasonal averages will prevail in the wake of this cold front. Troughing will take shape over the eastern US as we head into Monday. A cold front will push southward at this time and back into the CWA on Monday afternoon, giving us another chance of thunderstorms through the day and into the evening. There is some disagreement with the placement of the front however; both global models indicate the same general timing of the feature. The front will wash out as we head into Tuesday and a ridge will begin to build over the western states. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1119 AM MDT Wed Jul 20 2016 VFR conditions will continue through the TAF period at both KGLD and KMCK terminals. Thunderstorm activity may develop along a surface trough in eastern colorado and move into northwest Kansas and southwest Nebraska. Confidence was too low to include mention in either KGLD or KMCK TAF as coverage may remain very isolated. Winds should remain less than 12kt through the TAF period, though a LLJ developing tonight may lead to low level wind shear developing at both terminals. Confidence was higher in wind shear at KMCK, so I left mention out of KGLD for now. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory until 7 PM CDT Friday for KSZ002>004-014>016-028- 029. CO...NONE. NE...Heat Advisory until 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...LOCKHART LONG TERM...TL AVIATION...DR
Area Forecast Discussion National Weather Service Dodge City KS 1200 PM CDT WED JUL 20 2016 ...Updated Aviation... .SHORT TERM...(Today and tonight) Issued at 226 AM CDT Wed Jul 20 2016 For today, the heat continues with upper level warm ridging intact across the Central Plains. High temps will be dependent on 700 mb forecast temps that show not much change from yesterday. However more downslope surface winds will add a few degrees to highs today. Also with downslope and deep mixing, the dewpoints will mix out, so no heat headlines planned today. Highs will range from 101 west of Dodge to near 98 at Dodge City and around 101 from Medicine Lodge to Hays. South to southwest winds increase to 15 to 24 mph in the afternoon with a lee trough and clear skies. For tonight, south winds decrease to around 10 mph with clear skies. Overnight lows will range from around 70 far west near the Colorado border to the mid 70s across south central sections. .LONG TERM...(Thursday through Tuesday) Issued at 226 AM CDT Wed Jul 20 2016 For Thursday and Friday, the heat continues with 700 mb temps warming a few degrees. This will allow mix down temps to be a few degrees warmer and range from 100 to 104. However dewpoints below 65 are expected and likely not add to the heat index. Still these temps will be very close to heat advisory especially for south central sections where dewpoints will be the highest. Later shifts may need evaluate how much dewpoints mix out, and if heat advisories will be required for parts of the area. For the weekend into early next week. Shortwave troughs will traverse across the Plains with increasing chances for mainly late afternoon and evening scattered thunderstorms. These waves will allow the heat wave to break with highs back into the low to mid 90s from Sunday into Tuesday. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1200 PM CDT Wed Jul 20 2016 VFR/SKC through Thursday, with only a few cumulus each afternoon. SW winds gusting near 30 kts this afternoon, diminishing at sunset. Consensus of short term models again develops widespread low level wind shear starting around 06z, with 850 mb winds (LLJ) peaking around 45 kts. No changes Thursday; SKC and no convection with high pressure firmly in control. After 15z Thu, SW winds 15-25 kts at all airports. && .PRELIMINARY POINT TEMPS/POPS... DDC 98 74 101 74 / 0 0 0 10 GCK 101 72 101 71 / 0 0 0 10 EHA 100 72 101 71 / 0 0 0 10 LBL 100 73 103 72 / 0 0 0 10 HYS 101 75 102 74 / 0 0 0 10 P28 100 76 102 76 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Kruse LONG TERM...Kruse AVIATION...Turner
Area Forecast Discussion National Weather Service Dodge City KS 1200 PM CDT WED JUL 20 2016 ...Updated Aviation... .SHORT TERM...(Today and tonight) Issued at 226 AM CDT Wed Jul 20 2016 For today, the heat continues with upper level warm ridging intact across the Central Plains. High temps will be dependent on 700 mb forecast temps that show not much change from yesterday. However more downslope surface winds will add a few degrees to highs today. Also with downslope and deep mixing, the dewpoints will mix out, so no heat headlines planned today. Highs will range from 101 west of Dodge to near 98 at Dodge City and around 101 from Medicine Lodge to Hays. South to southwest winds increase to 15 to 24 mph in the afternoon with a lee trough and clear skies. For tonight, south winds decrease to around 10 mph with clear skies. Overnight lows will range from around 70 far west near the Colorado border to the mid 70s across south central sections. .LONG TERM...(Thursday through Tuesday) Issued at 226 AM CDT Wed Jul 20 2016 For Thursday and Friday, the heat continues with 700 mb temps warming a few degrees. This will allow mix down temps to be a few degrees warmer and range from 100 to 104. However dewpoints below 65 are expected and likely not add to the heat index. Still these temps will be very close to heat advisory especially for south central sections where dewpoints will be the highest. Later shifts may need evaluate how much dewpoints mix out, and if heat advisories will be required for parts of the area. For the weekend into early next week. Shortwave troughs will traverse across the Plains with increasing chances for mainly late afternoon and evening scattered thunderstorms. These waves will allow the heat wave to break with highs back into the low to mid 90s from Sunday into Tuesday. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1200 PM CDT Wed Jul 20 2016 VFR/SKC through Thursday, with only a few cumulus each afternoon. SW winds gusting near 30 kts this afternoon, diminishing at sunset. Consensus of short term models again develops widespread low level wind shear starting around 06z, with 850 mb winds (LLJ) peaking around 45 kts. No changes Thursday; SKC and no convection with high pressure firmly in control. After 15z Thu, SW winds 15-25 kts at all airports. && .PRELIMINARY POINT TEMPS/POPS... DDC 98 74 101 74 / 0 0 0 10 GCK 101 72 101 71 / 0 0 0 10 EHA 100 72 101 71 / 0 0 0 10 LBL 100 73 103 72 / 0 0 0 10 HYS 101 75 102 74 / 0 0 0 10 P28 100 76 102 76 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Kruse LONG TERM...Kruse AVIATION...Turner
Area Forecast Discussion National Weather Service Goodland KS 554 AM MDT WED JUL 20 2016 .SHORT TERM...(Today and tonight) Issued at 300 AM MDT Wed Jul 20 2016 Short term concerns are hot temperatures over the next few days with heat index maximums near 105 and heat index minimums around 75 with the possibility of thunderstorms each day. The large high pressure area aloft over the central United States flattens somewhat through the end of the week and retrogrades back over the southwest as a couple of short wave troughs lift out of the southwest and track up the back side of the ridge and a larger upper trough tracks through the northwest U.S. along the Canadian border. The upper trough emerges east of the Rockies Friday night over southern Saskatchewan and eastern Montana. A persistent surface trough remains generally in place over the western portion of the forecast area through Friday with mainly south winds across the region ahead of the trough. As the upper ridge flattens over the central U.S. and the upper trough moves east of the northern Rockies by late Friday and over the northern plains by Friday night, a cold front is expected to begin moving into the central high plains region. Temperatures across the forecast area will remain hot ahead of this front with highs well in the 90s to lower 100s and lows in the 60s to middle 70s. Combined with dewpoints that remain mostly in the lower 60s across the northern and eastern extent of the forecast area, expect maximum heat index values near 105 with minimum heat index values in the middle 70s across the same area. The heat advisory remains in effect for those areas and looks to be on track, so will leave it as is. With short wave impulses moving east of the Rockies and across the plains each day with moisture convergence and increased instabilty in the vicinity of the surface trough over the western sections of the forecast area, expect isolated to scattered thunderstorms developing west of the forecast area each afternoon and evening to move eastward through the evening and overnight hours with storms dissipating as they move further east into the ridge. .LONG TERM...(Saturday through Tuesday) Issued at 233 AM MDT Wed Jul 20 2016 Ridge breaks down and slides westward as we head into Saturday and Sunday. A nearly stationary theta-e boundary associated with a cold front will be in place from southwest to northeast across the CWA on Saturday and will strengthen as we head into Sunday, allowing for slgt chc to chc PoPs across the area mainly during the mid afternoon through late evening. Surface low pressure will remain in place in the vicinity of this boundary due to lee side upper level divergent flow. CAPE values are expected to be up to 1600 J/Kg and shear will be very low thus severe potential will be limited to gusty winds and perhaps large hail in the presence of DCAPE values around 700 to 1200 J/Kg. Much cooler temperatures much closer to seasonal averages will prevail in the wake of this cold front. Troughing will take shape over the eastern US as we head into Monday. A cold front will push southward at this time and back into the CWA on Monday afternoon, giving us another chance of thunderstorms through the day and into the evening. There is some disagreement with the placement of the front however; both global models indicate the same general timing of the feature. The front will wash out as we head into Tuesday and a ridge will begin to build over the western states. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 436 AM MDT Wed Jul 20 2016 VFR conditions will persist at GLD and MCK through the TAF period. South winds will become light through the day with LLWS possible after 06Z tonight. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory from noon today to 7 PM CDT Friday for KSZ002>004- 014>016-028-029. CO...NONE. NE...Heat Advisory from 11 AM MDT /noon CDT/ this morning to 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...LOCKHART LONG TERM...TL AVIATION...LOCKHART
Area Forecast Discussion National Weather Service Dodge City KS 654 AM CDT WED JUL 20 2016 ...Updated for aviation discussion... .SHORT TERM...(Today and tonight) Issued at 226 AM CDT Wed Jul 20 2016 For today, the heat continues with upper level warm ridging intact across the Central Plains. High temps will be dependent on 700 mb forecast temps that show not much change from yesterday. However more downslope surface winds will add a few degrees to highs today. Also with downslope and deep mixing, the dewpoints will mix out, so no heat headlines planned today. Highs will range from 101 west of Dodge to near 98 at Dodge City and around 101 from Medicine Lodge to Hays. South to southwest winds increase to 15 to 24 mph in the afternoon with a lee trough and clear skies. For tonight, south winds decrease to around 10 mph with clear skies. Overnight lows will range from around 70 far west near the Colorado border to the mid 70s across south central sections. .LONG TERM...(Thursday through Tuesday) Issued at 226 AM CDT Wed Jul 20 2016 For Thursday and Friday, the heat continues with 700 mb temps warming a few degrees. This will allow mix down temps to be a few degrees warmer and range from 100 to 104. However dewpoints below 65 are expected and likely not add to the heat index. Still these temps will be very close to heat advisory especially for south central sections where dewpoints will be the highest. Later shifts may need evaluate how much dewpoints mix out, and if heat advisories will be required for parts of the area. For the weekend into early next week. Shortwave troughs will traverse across the Plains with increasing chances for mainly late afternoon and evening scattered thunderstorms. These waves will allow the heat wave to break with highs back into the low to mid 90s from Sunday into Tuesday. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 653 AM CDT Wed Jul 20 2016 A surface trough will remain in the lee of the Rockies through the period, resulting in a continuation of south winds. The strongest winds will be during peak heating in the afternoon. VFR conditions will persist. && .PRELIMINARY POINT TEMPS/POPS... DDC 98 74 101 74 / 0 0 0 10 GCK 101 72 101 71 / 0 0 0 10 EHA 101 72 101 71 / 0 0 0 10 LBL 100 73 103 72 / 0 0 0 10 HYS 101 75 102 74 / 0 0 0 10 P28 100 76 102 76 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Kruse LONG TERM...Kruse AVIATION...Finch
Area Forecast Discussion National Weather Service Wichita KS 629 AM CDT WED JUL 20 2016 .SYNOPSIS... Issued at 303 AM CDT Wed Jul 20 2016 Impressive anticyclonic motion is evident on this mornings water vapor loop as upper-level ridging holds strong across the central CONUS. Cutoff energy continues to persist across the Pacific Northwest, with additional shortwave energy beginning to dig south across the Canadian Rocky Mountains. && .SHORT TERM...(Today through Friday night) Issued at 303 AM CDT Wed Jul 20 2016 No changes have been made to the inherited heat headlines once again. With many locations coming up short of the heat advisories criteria these past few days, have opted to leave the excessive heat warning as is for now. Over the next few days a possible expansion of the heat advisory and excessive heat warning will need to be monitored as the more substantial heat arrives. The heat really starts to crank up for the rest of the work week and into the weekend, with 1000-850mb partial thickness values easily supportive of widespread lower 100s across central and south central Kansas as 25-30C air advects northeast across the region each day. As we progress through the end of the work week, the dry, warm air aloft with gradually work its way further east. Therefore, expect dewpoints to mix out a bit more each day across the area. The worst heat indices still look to occur on Thursday when the feels like temperature may approach the 110 degree mark across portions of central Kansas. This does not seem unreasonable given the fact that temperatures are expected to approach the 104-105 degree mark. Unfortunately, little relief will be felt at night with overnight lows only dropping into the middle to upper 70s. There is a slight chance Friday night into Saturday for an isolated storm or two, but confidence is not high enough at this time to include any mentions higher than a slight chances across far central Kansas. .LONG TERM...(Saturday through Tuesday) Issued at 303 AM CDT Wed Jul 20 2016 As the upper-level ridge begins to break down towards the beginning of the weekend we could still see the 100 degree temperatures continue through the day on Saturday. However, the big question will be at that point how low dewpoints will get with ample mixing spanning numerous prior days. Given the uncertainty have opted to hold off on extending heat headlines into Saturday for now. With the above mentioned upper-level ridge breaking down as a trough begins to dig across the Northern Plains, a frontal boundary will begin to slowly drop south across the region. This will bring periodic chances for storms towards the end of the weekend and into the first half of the work week. Accompanying these chances for precipitation, temperatures will "cool down" to near normal for this time of year. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 629 AM CDT Wed Jul 20 2016 VFR conditions are expected for the next 24 hours. Could see some fair weather cumulus near the KCNU, KSLN and KICT Tafs. Ketcham && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 100 77 101 77 / 0 0 0 10 Hutchinson 100 77 102 77 / 0 0 0 10 Newton 99 77 101 77 / 0 0 0 10 ElDorado 97 77 99 77 / 0 0 0 0 Winfield-KWLD 98 77 100 77 / 0 0 0 0 Russell 102 76 104 75 / 0 0 0 10 Great Bend 101 75 104 75 / 0 0 0 10 Salina 101 78 105 78 / 0 0 0 10 McPherson 100 77 103 76 / 0 0 0 10 Coffeyville 96 75 98 75 / 10 0 0 0 Chanute 95 76 97 76 / 10 0 0 0 Iola 95 76 97 76 / 10 0 0 0 Parsons-KPPF 95 76 97 76 / 10 0 0 0 && .ICT Watches/Warnings/Advisories... Heat Advisory until 8 PM CDT Friday for KSZ051-068-069-083- 092>096-098>100. Heat Advisory from noon today to 8 PM CDT Friday for KSZ033-048- 050-067-082-091. Excessive Heat Warning until 8 PM CDT Friday for KSZ049-052-053- 070>072. && $$ SYNOPSIS...JMR SHORT TERM...JMR LONG TERM...JMR AVIATION...BDK
Area Forecast Discussion National Weather Service Goodland KS 350 AM MDT WED JUL 20 2016 .SHORT TERM...(Today and tonight) Issued at 300 AM MDT Wed Jul 20 2016 Short term concerns are hot temperatures over the next few days with heat index maximums near 105 and heat index minimums around 75 with the possibility of thunderstorms each day. The large high pressure area aloft over the central United States flattens somewhat through the end of the week and retrogrades back over the southwest as a couple of short wave troughs lift out of the southwest and track up the back side of the ridge and a larger upper trough tracks through the northwest U.S. along the Canadian border. The upper trough emerges east of the Rockies Friday night over southern Saskatchewan and eastern Montana. A persistent surface trough remains generally in place over the western portion of the forecast area through Friday with mainly south winds across the region ahead of the trough. As the upper ridge flattens over the central U.S. and the upper trough moves east of the northern Rockies by late Friday and over the northern plains by Friday night, a cold front is expected to begin moving into the central high plains region. Temperatures across the forecast area will remain hot ahead of this front with highs well in the 90s to lower 100s and lows in the 60s to middle 70s. Combined with dewpoints that remain mostly in the lower 60s across the northern and eastern extent of the forecast area, expect maximum heat index values near 105 with minimum heat index values in the middle 70s across the same area. The heat advisory remains in effect for those areas and looks to be on track, so will leave it as is. With short wave impulses moving east of the Rockies and across the plains each day with moisture convergence and increased instabilty in the vicinity of the surface trough over the western sections of the forecast area, expect isolated to scattered thunderstorms developing west of the forecast area each afternoon and evening to move eastward through the evening and overnight hours with storms dissipating as they move further east into the ridge. .LONG TERM...(Saturday through Tuesday) Issued at 233 AM MDT Wed Jul 20 2016 Ridge breaks down and slides westward as we head into Saturday and Sunday. A nearly stationary theta-e boundary associated with a cold front will be in place from southwest to northeast across the CWA on Saturday and will strengthen as we head into Sunday, allowing for slgt chc to chc PoPs across the area mainly during the mid afternoon through late evening. Surface low pressure will remain in place in the vicinity of this boundary due to lee side upper level divergent flow. CAPE values are expected to be up to 1600 J/Kg and shear will be very low thus severe potential will be limited to gusty winds and perhaps large hail in the presence of DCAPE values around 700 to 1200 J/Kg. Much cooler temperatures much closer to seasonal averages will prevail in the wake of this cold front. Troughing will take shape over the eastern US as we head into Monday. A cold front will push southward at this time and back into the CWA on Monday afternoon, giving us another chance of thunderstorms through the day and into the evening. There is some disagreement with the placement of the front however; both global models indicate the same general timing of the feature. The front will wash out as we head into Tuesday and a ridge will begin to build over the western states. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1030 PM MDT Tue Jul 19 2016 For KGLD and KMCK, vfr conditions expected through the period. Only a few mid and high clouds expected through the period. Winds begin the period from the south to southeast occasionally gusting near 20kts. This continues overnight with a slight veering to the southwest around 10kts or so after 14z. Both terminals will see wind shear in the 07z-12z timeframe. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory from noon today to 7 PM CDT Friday for KSZ002>004- 014>016-028-029. CO...NONE. NE...Heat Advisory from 11 AM MDT /noon CDT/ this morning to 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...LOCKHART LONG TERM...TL AVIATION...99
Area Forecast Discussion National Weather Service Goodland KS 237 AM MDT WED JUL 20 2016 .SHORT TERM...(This afternoon through Wednesday) Issued at 147 PM MDT Tue Jul 19 2016 Early afternoon WV imagery and RAP upper level analysis show large scale ridge centered over the plains dominating the pattern across the US. Moist monsoonal plume is wrapping around the western extent of ridge into the Rockies. At the surface; low pressure is in place across eastern Colorado with a trough axis extending from northeast Colorado and across northern Kansas. Southwest flow is in place across much of our cwa. This afternoon-Wednesday: Mean storm track remains well west of our CWA with focus mainly in the central Rockies. A few weak shortwaves may try rotating towards the northwest part of our CWA. West and northwest parts of our CWA (near surface trough) also have better chance to see any thunderstorm activity due to weaker CAP and better instability. Further south and east in our CWA guidance shows a stronger CAP and eventually a significant decrease in CAPE as profiles warm and dry out during the afternoon periods. Strongest precip signal in guidance matches with these trends (northwest). A slightly stronger shortwave and shift in trough axis Wednesday (as indicated by some models) may support a few thunderstorms moving a little further east-southeast Wednesday afternoon (far northwest Kansas). Regarding temperatures/heat indices: Air mass aloft is only expected to become warmer and consensus shows highs 2-4F warmer than today. A major question on heat indices is Tds (which may mix lower in our west). As Tds decrease below 60 heat indices actually decrease from ambient temperature. Td recovery during the nighttime periods we will see overnight heat indices in the 68-76 range (minimum) which is quite mild for our CWA. There may be a few counties along western periphery of current heat advisory that remain below "exact" advisory criteria, but it is close enough and considering the very warm nighttime heat indices and several days in a row of the hot temperatures the decision was made to upgrade watch to heat advisory. Consecutive day requirement is not expected to be met for issuance of heat warning at this time, so advisory was favored. .LONG TERM...(Saturday through Tuesday) Issued at 233 AM MDT Wed Jul 20 2016 Ridge breaks down and slides westward as we head into Saturday and Sunday. A nearly stationary theta-e boundary associated with a cold front will be in place from southwest to northeast across the CWA on Saturday and will strengthen as we head into Sunday, allowing for slgt chc to chc PoPs across the area mainly during the mid afternoon through late evening. Surface low pressure will remain in place in the vicinity of this boundary due to lee side upper level divergent flow. CAPE values are expected to be up to 1600 J/Kg and shear will be very low thus severe potential will be limited to gusty winds and perhaps large hail in the presence of DCAPE values around 700 to 1200 J/Kg. Much cooler temperatures much closer to seasonal averages will prevail in the wake of this cold front. Troughing will take shape over the eastern US as we head into Monday. A cold front will push southward at this time and back into the CWA on Monday afternoon, giving us another chance of thunderstorms through the day and into the evening. There is some disagreement with the placement of the front however; both global models indicate the same general timing of the feature. The front will wash out as we head into Tuesday and a ridge will begin to build over the western states. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1030 PM MDT Tue Jul 19 2016 For KGLD and KMCK, vfr conditions expected through the period. Only a few mid and high clouds expected through the period. Winds begin the period from the south to southeast occasionally gusting near 20kts. This continues overnight with a slight veering to the southwest around 10kts or so after 14z. Both terminals will see wind shear in the 07z-12z timeframe. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory from noon today to 7 PM CDT Friday for KSZ002>004- 014>016-028-029. CO...NONE. NE...Heat Advisory from 11 AM MDT /noon CDT/ this morning to 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...DR LONG TERM...TL AVIATION...99
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
251 AM CDT WED JUL 20 2016 .SHORT TERM...(Today and Tonight) Issued at 251 AM CDT WED JUL 20 2016 A warm night tonight with temperatures still near 80 in many locations. A little more southerly wind in past days likely keeping the boundary layer more more mixed than previous nights. Convection tonight is also farther north and west, leaving the forecast area under mostly clear skies at this hour. Temperatures rise a degree or two from yesterdays numbers, with highs in the middle 90s to near 100. Heat indicies running from 100-109F across the area as the excessive heat warning continues. A little more wind today but not likely to make it feel much cooler. Lows tonight fall into the middle 70s to near 80. .LONG TERM...(Thursday through Tuesday) Issued at 251 AM CDT WED JUL 20 2016 Only minor changes to previous forecast. Upper high still in place into the late week before weakening late Friday into the weekend. Southwest low level flow and general subsidence keep the hot conditions in place with little opportunity for precipitation. 850mb temps continue their rise into Thursday and remain fairly steady into Saturday with the main challenges being in the specifics of the air and wet bulb temps. Went on the warmer and drier side of guidance given model performance in recent similar environments. Heat index values still looking to reach 103 to 110 through Saturday. Upper wave passing over the northern states still looks to drag a cold front into the area Saturday night into Sunday for at least cooler temps and some chance for precipitation. Chances should linger into Tuesday as another wave takes a similar track to the north, with isentropic lift resulting. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1123 PM CDT TUE JUL 19 2016 VFR conditions look to prevail due to the upper ridge overhead and LLWS continues to look to marginal to include in the forecast. && .TOP Watches/Warnings/Advisories... Excessive Heat Warning until 7 PM CDT Saturday for KSZ008>012- 020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...67 LONG TERM...65 AVIATION...Wolters
Area Forecast Discussion National Weather Service Dodge City KS 235 AM CDT WED JUL 20 2016 ...Updated for Short and Long Term... .SHORT TERM...(Today and tonight) Issued at 226 AM CDT Wed Jul 20 2016 For today, the heat continues with upper level warm ridging intact across the Central Plains. High temps will be dependent on 700 mb forecast temps that show not much change from yesterday. However more downslope surface winds will add a few degrees to highs today. Also with downslope and deep mixing, the dewpoints will mix out, so no heat headlines planned today. Highs will range from 101 west of Dodge to near 98 at Dodge City and around 101 from Medicine Lodge to Hays. South to southwest winds increase to 15 to 24 mph in the afternoon with a lee trough and clear skies. For tonight, south winds decrease to around 10 mph with clear skies. Overnight lows will range from around 70 far west near the Colorado border to the mid 70s across south central sections. .LONG TERM...(Thursday through Tuesday) Issued at 226 AM CDT Wed Jul 20 2016 For Thursday and Friday, the heat continues with 700 mb temps warming a few degrees. This will allow mix down temps to be a few degrees warmer and range from 100 to 104. However dewpoints below 65 are expected and likely not add to the heat index. Still these temps will be very close to heat advisory especially for south central sections where dewpoints will be the highest. Later shifts may need evaluate how much dewpoints mix out, and if heat advisories will be required for parts of the area. For the weekend into early next week. Shortwave troughs will traverse across the Plains with increasing chances for mainly late afternoon and evening scattered thunderstorms. These waves will allow the heat wave to break with highs back into the low to mid 90s from Sunday into Tuesday. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1137 PM CDT Tue Jul 19 2016 VFR conditions will prevail with high pressure ridging and a surface lee trough. Light southeast winds become south to southwesterly at 15-24kt after 15Z. LLWS is forecast through 12-15Z with winds off the deck around 40kt. && .PRELIMINARY POINT TEMPS/POPS... DDC 98 74 101 74 / 0 0 0 10 GCK 100 72 101 71 / 0 0 0 10 EHA 98 72 101 71 / 0 0 0 10 LBL 99 73 103 72 / 0 0 0 10 HYS 101 75 102 74 / 0 0 0 10 P28 100 76 102 76 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Kruse LONG TERM...Kruse AVIATION...Kruse
Area Forecast Discussion National Weather Service Dodge City KS 235 AM CDT WED JUL 20 2016 ...Updated for Short and Long Term... .SHORT TERM...(Today and tonight) Issued at 226 AM CDT Wed Jul 20 2016 For today, the heat continues with upper level warm ridging intact across the Central Plains. High temps will be dependent on 700 mb forecast temps that show not much change from yesterday. However more downslope surface winds will add a few degrees to highs today. Also with downslope and deep mixing, the dewpoints will mix out, so no heat headlines planned today. Highs will range from 101 west of Dodge to near 98 at Dodge City and around 101 from Medicine Lodge to Hays. South to southwest winds increase to 15 to 24 mph in the afternoon with a lee trough and clear skies. For tonight, south winds decrease to around 10 mph with clear skies. Overnight lows will range from around 70 far west near the Colorado border to the mid 70s across south central sections. .LONG TERM...(Thursday through Tuesday) Issued at 226 AM CDT Wed Jul 20 2016 For Thursday and Friday, the heat continues with 700 mb temps warming a few degrees. This will allow mix down temps to be a few degrees warmer and range from 100 to 104. However dewpoints below 65 are expected and likely not add to the heat index. Still these temps will be very close to heat advisory especially for south central sections where dewpoints will be the highest. Later shifts may need evaluate how much dewpoints mix out, and if heat advisories will be required for parts of the area. For the weekend into early next week. Shortwave troughs will traverse across the Plains with increasing chances for mainly late afternoon and evening scattered thunderstorms. These waves will allow the heat wave to break with highs back into the low to mid 90s from Sunday into Tuesday. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1137 PM CDT Tue Jul 19 2016 VFR conditions will prevail with high pressure ridging and a surface lee trough. Light southeast winds become south to southwesterly at 15-24kt after 15Z. LLWS is forecast through 12-15Z with winds off the deck around 40kt. && .PRELIMINARY POINT TEMPS/POPS... DDC 98 74 101 74 / 0 0 0 10 GCK 100 72 101 71 / 0 0 0 10 EHA 98 72 101 71 / 0 0 0 10 LBL 99 73 103 72 / 0 0 0 10 HYS 101 75 102 74 / 0 0 0 10 P28 100 76 102 76 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Kruse LONG TERM...Kruse AVIATION...Kruse
Area Forecast Discussion National Weather Service Wichita KS 1200 AM CDT WED JUL 20 2016 .SYNOPSIS... Issued at 303 PM CDT Tue Jul 19 2016 Upper ridging continues to build over the central/southern Plains with shortwave energy coming onshore over the Pacific NW. Meanwhile, another shortwave trough is tracking over eastern Quebec. At the surface, high pressure is centered over the Great Lakes region with weak lee troughing over eastern CO/western Nebraska. && .SHORT TERM...(This evening through Friday night) Issued at 303 PM CDT Tue Jul 19 2016 Upper ridging will continue to strengthen over the central/southern Plains through Thu with 850mb temps warming into the 25-30C range. We should start to see numerous sites get into the low 100s starting Wed and continuing through Fri. Will maintain heat headlines through Fri but with dewpoints mixing out a bit more each day, still feel confident that we are not looking at 110 degree heat indices. In addition, gusty south and southwest winds will also help provide some relief. As mid level temps and associated capping continue to increase, should see a decrease in MCS activity through Fri over the central Plains, so confidence is high in keeping a dry forecast going. .LONG TERM...(Saturday through Tuesday) Issued at 303 PM CDT Tue Jul 19 2016 Both ECMWF and GFS agree in tracking a shortwave across the northern Rockies and into the northern Plains by Sat afternoon. This should help break down the upper ridging over the southern Rockies into the Plains. There is also some agreement in a front trying to make its way down into northern/western KS by late Sat afternoon. So will start to slowly bring storm chances back Sat for parts of central KS and area wide by Sun. However, not confident enough at this point to go with anything higher than a slight chance due to lack of larger scale forcing. As far as temps go, they look to moderate back closer to seasonal normals by Sun. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1158 PM CDT Tue Jul 19 2016 VFR conditions are forecast at all sites throughout the period. Winds should increase in the morning with cumulus redeveloping at most locations. -Howerton && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 76 100 76 102 / 0 0 0 0 Hutchinson 75 100 76 103 / 0 0 0 10 Newton 75 99 76 101 / 0 0 0 0 ElDorado 75 97 76 99 / 0 0 0 0 Winfield-KWLD 76 98 76 100 / 0 0 0 0 Russell 74 102 75 104 / 0 0 0 10 Great Bend 74 101 75 104 / 0 0 0 10 Salina 76 101 77 103 / 0 0 0 0 McPherson 75 100 76 103 / 0 0 0 0 Coffeyville 75 96 75 98 / 20 10 0 0 Chanute 75 95 76 97 / 10 10 0 0 Iola 75 95 76 97 / 10 10 0 0 Parsons-KPPF 75 95 75 98 / 10 10 0 0 && .ICT Watches/Warnings/Advisories... Heat Advisory until 8 PM CDT Friday for KSZ051-068-069-083- 092>096-098>100. Heat Advisory from noon Wednesday to 8 PM CDT Friday for KSZ033- 048-050-067-082-091. Excessive Heat Warning until 8 PM CDT Friday for KSZ049-052-053- 070>072. && $$ SHORT TERM...RBL LONG TERM...RBL AVIATION...ADK
Area Forecast Discussion National Weather Service Dodge City KS 1140 PM CDT TUE JUL 19 2016 ...Updated for Aviation... .SHORT TERM...(This evening through Wednesday) Issued at 1223 PM CDT Tue Jul 19 2016 There isn`t much to say, once the upper high takes over. Upper high centered near the Ozarks into Oklahoma this afternoon, with anvil debris from last night`s MCS in Nebraska trapped in the anticyclonic circulation aloft. Between the dissipating cirrus, a lack of a good downslope component, and continued green vegetation/transpiration and high dewpoints, most locales will fall short of 100 again this afternoon. Wednesday...No change in the pattern means no change in the weather. Hot and dry. Models warm 850 mb temps on average another 2 degrees on Wednesday, and with a decent SWly surface wind component gusting near 30 mph, more locations will crack the 100 degree mark. .LONG TERM...(Wednesday night through Tuesday) Issued at 225 PM CDT Tue Jul 19 2016 Strong high pressure aloft will deliver three very hot afternoons Thursday, Friday and Saturday. MEX/GFS guidance still looks a bit too hot, but nonetheless, widespread triple digit heat is anticipated across SW KS as 850 mb temperatures max out around 30C. Next several shifts will need to determine the need for a heat advisory during these afternoons, to match our WFO neighbors to our east and north. The apparent temperature (heat index) grids currently indicate only the far SE zones will flirt with advisory criteria (105) for a couple hours Wednesday, followed by about the eastern 1/2 of the CWA near heat advisory criteria Thursday afternoon. Since Wednesday is marginal, will defer to later shifts on a heat advisory for Thursday. Some of our far eastern zones have a forecasted heat index of 107 in the grids Thursday afternoon, so a heat advisory is likely. Widespread subsidence will keep all zones dry on Thursday. Heights gradually lower on Friday, which may be enough for an isolated thunderstorm across the northern zones as 12z ECMWF suggests. High pressure weakens further over the weekend, allowing for a slow reduction in afternoon temperatures and a gradual upswing in thunderstorm coverage. Upper high pressure will be repositioned well west of SW KS starting Saturday, and remain that way through mid week next week. The return of NW flow aloft ensures there will be a chance of a thunderstorm in SW KS each day, as indicated by the CR-init pop grids. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1137 PM CDT Tue Jul 19 2016 VFR conditions will prevail with high pressure ridging and a surface lee trough. Light southeast winds become south to southwesterly at 15-24kt after 15Z. LLWS is forecast through 12-15Z with winds off the deck around 40kt. && .PRELIMINARY POINT TEMPS/POPS... DDC 73 100 74 103 / 0 0 0 10 GCK 71 100 72 102 / 0 0 0 10 EHA 69 101 71 101 / 0 0 0 10 LBL 71 101 71 102 / 0 0 0 10 HYS 73 101 75 103 / 0 0 0 10 P28 74 100 76 104 / 0 0 0 0 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Turner LONG TERM...Turner AVIATION...Kruse
Area Forecast Discussion National Weather Service Goodland KS 1035 PM MDT TUE JUL 19 2016 .SHORT TERM...(This afternoon through Wednesday) Issued at 147 PM MDT Tue Jul 19 2016 Early afternoon WV imagery and RAP upper level analysis show large scale ridge centered over the plains dominating the pattern across the US. Moist monsoonal plume is wrapping around the western extent of ridge into the Rockies. At the surface; low pressure is in place across eastern Colorado with a trough axis extending from northeast Colorado and across northern Kansas. Southwest flow is in place across much of our cwa. This afternoon-Wednesday: Mean storm track remains well west of our CWA with focus mainly in the central Rockies. A few weak shortwaves may try rotating towards the northwest part of our CWA. West and northwest parts of our CWA (near surface trough) also have better chance to see any thunderstorm activity due to weaker CAP and better instability. Further south and east in our CWA guidance shows a stronger CAP and eventually a significant decrease in CAPE as profiles warm and dry out during the afternoon periods. Strongest precip signal in guidance matches with these trends (northwest). A slightly stronger shortwave and shift in trough axis Wednesday (as indicated by some models) may support a few thunderstorms moving a little further east-southeast Wednesday afternoon (far northwest Kansas). Regarding temperatures/heat indices: Air mass aloft is only expected to become warmer and consensus shows highs 2-4F warmer than today. A major question on heat indices is Tds (which may mix lower in our west). As Tds decrease below 60 heat indices actually decrease from ambient temperature. Td recovery during the nighttime periods we will see overnight heat indices in the 68-76 range (minimum) which is quite mild for our CWA. There may be a few counties along western periphery of current heat advisory that remain below "exact" advisory criteria, but it is close enough and considering the very warm nighttime heat indices and several days in a row of the hot temperatures the decision was made to upgrade watch to heat advisory. Consecutive day requirement is not expected to be met for issuance of heat warning at this time, so advisory was favored. .LONG TERM...(Wednesday night through Tuesday) Issued at 213 PM MDT Tue Jul 19 2016 Overall, not much has changed in the long term. Hot temperatures are still the main story in the midterm while precipitation chances persist throughout the extended. Wednesday night through Friday, high pressure dominates the pattern. Above normal temperatures are anticipated with highs from the upper 90s to the low 100s on both Thursday and Friday, with Thursday being the hotter day for most locations. With dewpoint temperatures in the lower 60s, heat indices will be around 105 generally east of a line from Russell Springs, Kansas to Benkelman, Nebraska. This has warranted a heat headline for these locations. As mentioned in the short term discussion, the watch has been upgraded to a heat advisory (beginning Wednesday afternoon) and extended to cover through Friday afternoon. Expect somewhat dry conditions for the majority of the area, with only slight chances for convection each afternoon/evening as monsoonal moisture filters into the region along the western side of the ridge and disturbances pass through the upper flow. Friday night and the weekend, the ridge across the CONUS breaks down as a trough tracks from the Pacific Northwest and across the northern Plains, sending a cold front south. Will see more seasonal temperatures over the weekend. With a boundary nearby, expect thunderstorm chances through the weekend. Early next week, guidance differs on how the pattern develops. Consensus seems to be that the high pressure retreats to the west, bringing more of a west/northwest flow to the region. Some perturbations round the northern side of the high, traveling from the Rockies to the High Plains. This setup generates an opportunity for additional precipitation as the trough impacting the region during the weekend continues to push towards New England. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1030 PM MDT Tue Jul 19 2016 For KGLD and KMCK, vfr conditions expected through the period. Only a few mid and high clouds expected through the period. Winds begin the period from the south to southeast occasionally gusting near 20kts. This continues overnight with a slight veering to the southwest around 10kts or so after 14z. Both terminals will see wind shear in the 07z-12z timeframe. && .GLD Watches/Warnings/Advisories... KS...Heat Advisory from noon Wednesday to 7 PM CDT Friday for KSZ002>004-014>016-028-029. CO...NONE. NE...Heat Advisory from 11 AM MDT /noon CDT/ Wednesday to 6 PM MDT /7 PM CDT/ Friday for NEZ079>081. && $$ SHORT TERM...DR LONG TERM...JBH AVIATION...99
AREA FORECAST DISCUSSION
National Weather Service New Orleans LA
329 AM CDT WED JUL 20 2016 .Discussion... Main focus this week will continue to be impacts from an upper level ridge on the area in terms of temperatures and convection. This feature, centered near the Texas/Oklahoma border, will remain expanded across the entire southern half of the country throughout the week. Shower and thunderstorm coverage is expected to be fairly shunted as a result of high pressure subsidence. Rain chances for today similar to yesterday (20-30%) except meso models suggesting convection will be along and north of I-12 vs southwestern portions of the CWA as they were yesterday. Thinking timing will be similar to yesterday with most convection in the late morning to early afternoon then cutting off as the afternoon progresses. Temperatures will once again be a few degrees above normal. The current fcst max temps are at to slightly above MAV guidance. Dewpoints starting in the mid 70s should fall mainly into the lower 70s with daytime mixing. The timing of rising temps and falling dewpoints should keep heat indicies just below the 108 heat advisory criteria today. Thursday and Friday will be very similar from temp and pop perspective which is no surprise as the upper level pattern will for all intents and purposes be the same. The ridge will begin to weaken through the weekend and become more of a zonal pattern as a northern stream trough races along the US/Canada border. Temperatures will begin to fall back closer to normal and pops will increase more into the chance category. MEFFER && .AVIATION... Will continue VFR for all terminals today with the possibility of a TS being close by today. Any activity that gets started today should move in from the east and northeast. Updates may be needed during the day for one or two terminals. But conditions should be VFR for most sites through the 12z cycle. && .MARINE... Surface ridge extending westward across the northern gulf will keep winds generally east in the 5 to 15 knot range through much of the week. A weak easterly wave moving through the gulf today may be able to help a few sh/ts develop through the day. The strong upper/mid level ridge over the West is moving into the south-central conus. This upper/mid level high should be able to suppress most sh/ts activity by Thursday. This should hold through the weekend. The surface high will cause the local wind regime to be quite light at less than 10 knots and likely variable at times in direction. && .PRELIMINARY POINT TEMPS/POPS... MCB 95 76 96 75 / 30 10 20 10 BTR 96 77 96 77 / 20 10 30 10 ASD 95 78 94 78 / 30 10 20 10 MSY 94 79 95 79 / 20 10 20 10 GPT 95 78 93 78 / 30 10 20 10 PQL 92 74 93 74 / 30 10 20 10 && .LIX Watches/Warnings/Advisories... LA...None. GM...None. MS...None. GM...None. && $$
Area Forecast Discussion National Weather Service Shreveport LA 315 AM CDT WED JUL 20 2016 .DISCUSSION... An upper level high pressure system continues to be the main story early this morning, as it dominates across west TX, the Central Plains and the lower Mississippi Valley. The HRRR insists that isolated showers and thunderstorms will develop by late this morning across portions of Southwest AR, likely due to lingering outflow boundaries from yesterdays convection. Can not rule this out and therefore inserted slight chance pops across the aforementioned area. This aftn with the onset of daytime destabilization, additional isolated convection are possible particularly across North Louisiana, Southeast OK, Southwest AR and extreme East TX where highest PWATS will reside /PWATS aoa 2.00 inches/. Sparse diurnally driven precip is anticipated for the remainder of this week, but the main story will be the heat. Lack of widespread beneficial rainfall in recent weeks coupled with an upslope sfc regime, and the 500 mb UL ridge nearing 600 dam suggests temps having the ability to warm into the upper 90s today to the upper 90s and lower triple digit readings by the end of this week. This will push heat indices into the 105-109 degree range CWA-wide, with a few locales equating 110 degrees thus almost nearing Excessive Heat criteria /ex. KMLU heat index equated 110 degrees yesterday aftn/. The Heat Advisory in effect through 7 pm CDT tomorrow is definitely valid but as we have been doing the last few days, we may need to extend the advisory to include Friday. Thereafter, long term solutions continue to show the UL ridge weakening whilst drifting a bit Northward with the center noted near the Four-Corners region. This may open the door for disturbances once confined to the Northern CONUS to near the region, as well as Easterly waves from the Atlantic and Gulf to impinge on the region by early next week. All in all, this unsettled wx pattern could lead to increasing chances for rainfall. The Super-blended solution slight chance to low end chance pops early next week seems valid attm. If this does indeed come into fruition, the increased cloud cover could lead to slightly lowered /albeit still warm/ daytime temps /middle to upper 90s/ which may negate the need for a Heat Advisory next week. Keep in mind, things could change so be sure to stay tuned to the latest wx information. && .PRELIMINARY POINT TEMPS/POPS... SHV 98 79 99 79 / 20 10 10 10 MLU 98 78 99 77 / 20 10 20 10 DEQ 98 76 97 76 / 20 10 10 0 TXK 97 78 98 78 / 20 10 10 0 ELD 96 77 98 77 / 20 10 20 10 TYR 99 78 99 78 / 10 10 10 0 GGG 98 78 99 77 / 10 10 10 0 LFK 96 77 97 76 / 20 10 20 10 && .SHV Watches/Warnings/Advisories... AR...Heat Advisory until 7 PM CDT Thursday for ARZ050-051-059>061- 070>073. LA...Heat Advisory until 7 PM CDT Thursday for LAZ001>006-010>014- 017>022. OK...Heat Advisory until 7 PM CDT Thursday for OKZ077. TX...Heat Advisory until 7 PM CDT Thursday for TXZ096-097-108>112- 124>126-136>138-149>153-165>167. && $$ 29