Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/11/16
Area Forecast Discussion
National Weather Service Tucson AZ
900 PM MST FRI JUN 10 2016
.SYNOPSIS...Drier air starts to work in from the west on Saturday
pushing the best chance of storms to areas east of Tucson. A few
thunderstorms may occur near the New Mexico border on Sunday. Dry
conditions will prevail next week with a drier air mass over the
area. Daytime temperatures will remain near normal or a few degrees
below normal through Tuesday, then hotter temperatures return next
Wednesday and Thursday.
&&
.DISCUSSION...Showers and thunderstorms that developed across parts
of southeast Arizona today were starting to diminish in areal
coverage late this evening. The Safford area was hit the hardest
with high winds that caused power outages and downed trees in the
area. Several areas received heavy downpours and small hail that
covered the ground, especially on the southeast and northwest sides
of the greater Tucson metro. That said, just expecting a few
lingering showers and thunderstorms tonight with the activity
picking backup tomorrow afternoon. Not expecting the areal coverage
tomorrow to be as much as today. Will make some minor updates to the
current forecast for tonight. Otherwise, the rest of the forecast
looked on track.
&&
.AVIATION...VALID THRU 12/06Z.
Isolated -TSRA/-SHRA. Otherwise, cloud decks will generally range
from 10k-15k ft MSL. Surface wind mainly less than 10 kts except
near thunderstorms. Aviation discussion not updated for TAF
ammendments.
&&
.FIRE WEATHER...Expect scattered showers and thunderstorms again
Saturday. A few thunderstorms Sunday will likely be limited to the
higher terrain east of Tucson. Thunderstorm outflows will
occasionally produce brief strong, gusty and erratic winds. Dry
conditions will then prevail area-wide Monday through Friday of next
week. Daytime temperatures will be a few degrees below normal into
early next week, then hotter temperatures return Wednesday into next
Friday.
&&
.PREV DISCUSSION...Through the weekend, we will hang on to
POPS,especially Saturday although lesser than today, as an
approaching trough kicks the moisture to the east. Once the trough
passes through the region, high pressure will build back in for
warming temperatures during the middle to latter part of next week.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
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[top]
Area Forecast Discussion
National Weather Service Flagstaff AZ
318 PM MST FRI JUN 10 2016
.SYNOPSIS...Deeper subtropical moisture moving into Arizona from
the south will bring increasing chances for showers and
thunderstorms spreading northward through Saturday. Overnight
showers and thunderstorms will develop in response to an upper
level trough. Drier air will move in behind this trough with a
drying trend from west to east from Saturday to Sunday. Another
weak low moving through the Southwest region on Monday may bring a
few light showers to northern Arizona mainly along the Utah border
region. Otherwise a high pressure ridge will build in from Tuesday
onward bringing in more typical hot and dry June weather
conditions.
&&
.DISCUSSION...Strong convection is developing in Southeastern
Arizona this afternoon. Convective activity has been more limited
in northwestern Arizona due to a combination of lower moisture
levels and extensive cloud cover. The latest SREF, European and
American GFS models continue to show thunderstorm coverage
expanding northwestward through the evening hours as a upper level
trough moves northward across the state.
Deeper subtropical moisture continues to move up into Arizona
from the south this evening. An upper level trough moving around
the western edge of the ridge will help with both the moisture
advection into northern Arizona and provide some convective
forcing during the overnight hours. Due to the upper level
disturbance there is a chance for convection in southern Arizona
to send outflows northward into central Arizona with thunderstorms
riding the outflow convergence boundary. Around 8pm the upper
trough will move into Yavapai and Gila counties helping to
initiate evening showers and thunderstorms. This upper trough will
continue to move northward helping to spread nocturnal isolated to
scattered thunderstorm activity across the northern third of the
state.
Saturday and Sunday...As the trough moves northward drier Pacific
air moves into Arizona starting on Saturday into northwestern
Arizona while deeper moisture lingers in Apache and Navajo
counties. Expect a west to east drying trend through the weekend.
A cut off low approaching Arizona from the west will bring
increasing southwesterly winds on Sunday with sustained winds in
the 15 to 20 mph range along with gusts up to 30 mph.
On Monday...The cut off low will move across the Utah border
region with low chances for a few light showers and thunderstorms.
Tuesday through Friday...The subtropical ridge builds into the
Southwest with more typical June hot and dry weather forecast
into next weekend.
&&
.AVIATION...For the 00Z Package...Current radar imagery shows
scattered thunderstorms along the eastern Mogollon Rim and White
Mountains. Expect showers and thunderstorms to increase in
coverage and spread northward through the overnight hours. The
best chances for showers will be along and southwest of a line
from Greer to Winslow to Tusayan. Erratic winds with gusts to 45
kts will be possible near the strongest storms. In addition,
periods of MVFR visibilities are possible. Aviation discussion not
updated for TAF amendments.
&&
.FIRE WEATHER...Expect increasing high-based shower and thunderstorm
activity from southeast to northwest through the overnight hours.
Strong and erratic outflow winds are likely near storms. On
Saturday, lingering moisture will cause a round of scattered high-
based storms, primarily over higher terrain. Gusty southwest winds
and mainly dry conditions are expected on Sunday.
Monday through Wednesday...Slight chances for thunderstorms are
forecast Monday. Dry weather and a warming trend forecast Tuesday
and Wednesday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...Bohlin
AVIATION...RR
FIRE WEATHER...RR
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Tucson AZ
303 PM MST FRI JUN 10 2016
.SYNOPSIS...There is a good chance of showers and thunderstorms
for the remainder of this afternoon and into the evening hours, with
some of these storms producing areas of blowing dust due to strong
and gusty outflows. Localized heavy rain also possible. Drier air
starts to work in from the west on Saturday pushing the best chance
of storms to areas east of Tucson. A few thunderstorms may occur
near the New Mexico border on Sunday. Dry conditions will prevail
next week with a drier air mass over the area. Daytime temperatures
will remain near normal or a few degrees below normal through
Tuesday, then hotter temperatures return next Wednesday and Thursday.
&&
.DISCUSSION...Water vapor imagery shows high pressure over
the general vicinity of the four corners region. Meanwhile, an
inverted trough resides to our south over Sonora Mexico. Overnight,
convection developed/persisted across areas mainly along the
international border and moved west. The latest visible and IR
imagery shows remnants of this activity, with mid and high level
cloudiness covering mostly the western parts of the forecast area.
A persistent MCV is over extreme northwest Sonora and continues to
move rapidly to the west northwest.
This mornings 10/12Z KTWC sounding reveals a very wet airmass in
place with a PW of 1.46 inches, which is a record for this date. The
old record was 1.33 inches. In addition, decent flow in the column
with generally an easterly component in the entire profile. Enough
flow to help get storms organized, thus the inherited POP forecast
that shows high end scattered to likely category POP`s for most of
the forecast area. The only exception would be isolated activity
over the far western deserts of Pima county near Ajo and Organ Pipe.
In addition, some of the parameters from the sounding indicate a MU
Cape of nearly 1500 J/KG and a lifted index of minus 3.
The 12Z run of the U of A WRF NAM/GFS both show organized convection
developing initially over central areas, more specifically parts of
Santa Cruz and Pima counties and spreading to the northwest during
the late afternoon and early evening. The GFS is the more robust and
indicates explosion development beginning around the current time
over Santa Cruz county and then a large cluster/complex develops
over central Pima county and makes its way into Pinal county. After
4 pm, it shows additional development over eastern Pima and Western
Cochise county and this activity spreads north northwest into Graham
county and after 8 PM MST is mostly in the Phoenix area of
responsibility. The WRF/NAM solution shows initial development
around 2 to 3 PM MST (which is too slow) over eastern Pima county
and heads into Pinal county and areas beyond after around 6 PM MST
this evening. The latest run of the HRRR shows a similar solution
with early development over eastern Pima county and additional
development over Cochise, Graham and Greenlee counties, especially
after 11/00Z. So even though these solutions have the same general
theme, there are differences in the details. That said, have
generally gone with a sort of blend of these solutions, which means
scattered to low end likely category POP`s for a large part of the
forecast area, with the exception of western Pima county.
With the way the storms are developing today and with the
anticipated movement to the west northwest or northwest, the night
shift issued a blowing dust advisory for portions of central and
eastern Pima county and all of Pinal county, which will take effect
at 3 PM MST this afternoon and continue through 7 PM MST.
Through the weekend, we will hang on to POPS, especially Saturday
although lesser than today, as an approaching trough kicks the
moisture to the east. Once the trough passes through the region,
high pressure will build back in for warming temperatures during the
middle to latter part of next week.
&&
.AVIATION...VALID THRU 12/00Z.
Scattered -TSRA/-SHRA...wind gusts of 40-50 kts and visibilities
reduced to around 1-2SM with the stronger TSRA. Otherwise, cloud
decks will generally range from 10k-15k ft MSL. Surface wind mainly
less than 10 kts except near thunderstorms. Aviation discussion not
updated for TAF ammendments.
&&
.FIRE WEATHER...Expect scattered showers and thunderstorms this
afternoon and evening and again Saturday. A few thunderstorms Sunday
will likely be limited to the higher terrain east of Tucson.
Thunderstorm outflows will occasionally produce brief strong, gusty
and erratic winds. Dry conditions will then prevail area-wide Monday
through Friday of next week. Daytime temperatures will be a few
degrees below normal into early next week, then hotter temperatures
return Wednesday into next Friday.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...Blowing Dust Advisory in effect
until 7 PM this evening for AZZ502>506.
&&
$$
Mollere
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
609 PM CDT FRI JUN 10 2016
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Saturday)
Issued at 311 PM CDT FRI JUN 10 2016
Upper level ridge continues across the Central Plains this
afternoon. Weak upper trough was filling across central and
northeast Kansas this morning. Surface trough continues across the
western high plains with axis of mid to upper 60s dewpoints across
central and eastern Kansas. Afternoon cumulus has developed across
the area and should be on the decrease toward sunset with the loss
of heating. With little change in airmass since yesterday expect
low temperatures from the upper 60s to mid 70s overnight. On
Saturday, 850 mb temperatures warm a degree or two from today.
Forecast soundings suggest mixing down from around 850 mb with
highs mainly in the low to mid 90s. Afternoon dew points in the
upper 60s to around 70 will yield heat indices in the upper 90s to
around 100 degrees in the afternoon. With no forcing aloft or at
the surface and soundings showing weak cap remaining in place
Saturday afternoon, will keep the forecast dry.
.LONG TERM...(Saturday Night through Friday)
Issued at 311 PM CDT FRI JUN 10 2016
Last part of the weekend should remain dry and very warm with high
temps still in the 90s and heat indices into the mid to upper 90s.
Precip chances increase into Monday as and overnight complex of
storms appears to form over west central Nebraska and slowly make
its way near or into East Central Kansas by early morning. It will
be pushed along by a weak boundary and without significant forcing
aloft, the trend based on 12Z model data will be to decrease in
intensity and whatever rain and thunderstorms are left. Storms may
linger into the morning and early afternoon over the forecast area,
so have maintained chance POPs over most of the area. It isn`t until
the Tuesday time frame and overnight Wednesday that a tight compact
upper low forms and undergoes cyclogenesis as split southern stream
flow aloft ejects out of the Rockies into the Central Plains. Best
indication at this time is that the forcing aloft will increase over
western and northern portions of the forecast area giving the best
chance to strong to perhaps severe storms. With indications that
there will be a remnant EML in place, there could be more isolated
activity. But with the upper low deepening quickly, steep lapse
rates aloft with favorable shear, due to the upper low, could result
in mostly a severe hail and wind threat. Again, still not highly
confident in the overall set up or other forcing mechanisms such as
a possible modified dryline mixing into the area. Also, guidance
does vary too much at this time to be on the high end chance POPs.
Rest of the week after this does look dry once again with perhaps
slight chance POPs as the upper low essentially becomes cut off from
the upper flow aloft and eventually fills over the Ohio River
Valley. Meanwhile temps cool back to the mid to upper 80s by the
end of the week as northeast flow sets up with surface high
pressure in place.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 605 PM CDT FRI JUN 10 2016
VFR prevails at terminals. As southerly winds weaken below 7 kts
between 6 and 12Z, low level jet at 2 kft increases from the
southwest up to 35 kts. KMHK may approach llws conditions at 2 kft but
guidance remains too marginal for inclusion at this time. Will
address at next issuance.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Drake
AVIATION...Prieto
Area Forecast Discussion
National Weather Service Goodland KS
317 PM MDT FRI JUN 10 2016
.SHORT TERM...(This afternoon through Saturday)
Issued at 120 PM MDT Fri Jun 10 2016
Early afternoon WV imagery and RAP analysis indicates ridging
extending across Colorado with axis centered across our CWA. A
shortwave trough is east of our CWA. At the surface low pressure
is in place across eastern Colorado, with a secondary surface
trough axis near McCook Nebraska extending southeast through our
CWA.
This afternoon-Tonight: Weak forcing and moisture is rotating into
the rockies and has led to thunderstorm development across higher
terrain in south central Colorado. Some hi res guidance indicates
possible development and movement towards our western CWA, however
if this happens it will coincide with loss of daytime
heating/instability and confidence is low this would make it into
our CWA (particularly considering the mean storm motion and weak
flow aloft away from our CWA). Otherwise subsidence and a deep dry
air mass will preclude local thunderstorm development this
afternoon/evening. Relatively light winds and clear skies should
support another night of good radiational cooling, so expect
similar lows as last night (around 60F west to around 70F east).
Saturday: Upper level ridge shifts east while trough deepens in
this west. This may allow for a little more forcing to shift
eastward into our CWA, and there will be good instability in
place. Models are still indicating a very dry air mass in place,
and most guidance keeps dry conditions in place locally. Only
NMM/ARW supporting isolated thunderstorm activity Saturday
afternoon. I kept forecast dry for now, though I couldn`t rule of
a stray elevated thunderstorm. As the surface trough shifts east
and heights begin to fall, the air mass slowly "cools" over our
CWA. Temps aloft projected by guidance are very similar to was was
realized Thursday, and similar temperatures (low-mid 90s) would be
anticipated. This is a little lower than today, but still above
normal by 10-15 degrees.
.LONG TERM...(Saturday night through Friday)
Issued at 209 PM MDT Fri Jun 10 2016
The lee surface trough that strengthens along the Front Range on
Saturday begins moving east into the forecast area Saturday night
ahead of a cold front expected to push through the forecast area
on Sunday evening. This is accompanied by the short wave a aloft
that rides up the back side of the ridge late Saturday and then
tops the ridge late Sunday as it moves through Nebraska.
While models inconsistently hint at a few showers across the
central high plains region Saturday night, most likely as a few
storms form over the higher terrain of the Raton ridge and Palmer
divide, the highest probability of thunderstorms across the area
will occur late Sunday through early Monday morning as the short
wave trough moving through Nebraska turns around the apex of the
decreasing amplitude upper ridge and moves into eastern Kansas by
Monday. Model QPF is showing some possible heavy rains over south
central Nebraska and north central Kansas Sunday night. With
southerly flow extending from the Gulf of Mexico into the central
plains with dewpoints in the middle 60s over the eastern sections
of the forecast area, don`t feel this is out of line.
On Monday night through Tuesday night, the upper trough that has
been approaching through the southwestern U.S. will lift out
across the Rockies and Central High Plains region for another
round of storms mainly from late Monday through early Tuesday with
activity diminishing by Tuesday night.
As the trough deepens into a closed low over the northern plains
and moves out of the region and the upper ridge redevelops over
the High Plains, dry and hot temperatures return to the region
during the latter portion of next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1130 AM MDT Fri Jun 10 2016
VFR conditions will continue through the TAF period at KGLD and
KMCK. Surface trough will remain in place near the CO state line
with weak southerly gradient leading to winds below 12kt through
the first 12hr of the TAF period. Gradient begins to increase by
late morning Saturday, with gusts 20-30kt developing at KGLD at
the end of the TAF period.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
255 PM CDT THU JUN 9 2016
.SHORT TERM...(This Evening through Friday)
Issued at 255 PM CDT THU JUN 9 2016
Weak upper flow continues over the Central Plains this afternoon.
A weak upper trough was evident in the water vapor imagery over
western Nebraska into to the Texas Panhandle. Another weakening
circulation was moving across southeast Kansas and northeast
Oklahoma. Surface dry line was located over the high plains and
will move very little. Short term models differ with convection
this evening with the HRRR and and the RUC moving in some
weakening convection from the west during the late evening hours
into north central Kansas. The experimental HRRR keeps
precipitation to the west and diminishes it before moving to the
east of U.S. 81 Highway tonight. Will continue with small
precipitation chances in north central Kansas tonight. Lows
tonight will continue to be mild with readings in the upper 60s to
lower 70s.
Friday, Another good warm up is expected with the thermal ridge
extending into central Kansas have increased highs slightly into the
mid 90s with lower 90s elsewhere across northeast and east central
Kansas. The afternoon heat index will reach near 100 degrees across
parts of north central and northeast Kansas with the rest of the
area in the mid to upper 90s heat index. Weak upper trough/wave
moves across central and east Kansas on Friday. There is little in
the way of surface moisture convergence with the absence of any
boundary and a small EML remains in place through much of the day.
The upper trough fills as it moves east with the NAM the strongest
with the upper energy. Cannot rule out an isolated late afternoon
storm out in central Kansas, but confidence is not high enough to
include in forecast at this time.
.LONG TERM...(Friday Night through Thursday)
Issued at 255 PM CDT THU JUN 9 2016
For Friday night through Sunday, the main question with the
forecast is whether a lobe of vorticity gets trapped within the
upper ridge over the state. This idea was not in the operational
models yesterday, and now have almost a weak closed low aloft
near the forecast area during the weekend. Therefore confidence is
not all that great. Forecast soundings suggest the airmass will be
conditionally unstable with little inhibition to convection. So if
this piece of energy is near the area, there could be some
diurnally driven convection Saturday and/or Sunday. For now have
left POPs around 10 percent but later shifts may need to increase
chances if models continue to leave behind this energy within the
ridge. The forecast appears to be in good shape regarding forecast
temps as there isn`t much chance in the solution`s thermal
profiles. Highs are expected to be in the lower and middle 90s as
forecast soundings mix the boundary layer to around 825MB.
Continued southerly flow and dewpoints holding in the 60s
overnight support the lows forecast for temps bottoming out around
70 degrees.
Precip chances should be on the increase for Sunday night through
much of next week as the upper ridge breaks down and energy from
the west passes through the plains. An initial shortwave is
progged to pass through the central plains Sunday night and early
Monday. Then a more amplified system moves slowly across the
plains through Wednesday. The medium range models have come into
better agreement in closing off an upper low just north of the
forecast area by Wednesday. Think the better chances for precip
will be Monday through Tuesday night as the upper wave initially
moves out from the southern Rockies and a surface wave lifts
across the area. After Wednesday, there are question on where the
closed low drifts to and a possible dry slot working into the
area. Have held onto some small POPs Wednesday night and across
eastern KS for Thursday to account for the closed low in the
region. The models show temps trending cooler for next week as the
upper system moves through the region. However am a little
concerned temps could be to cool as cold raw model guidance seems
to be skewing the forecast cooler when there is no significant
cold air advection. This is probably due to the models generating
precip during these periods. Unless it is cloudy and raining all
day, it is hard to see why temps would not continue to be in the
lower 90s for Monday and Tuesday. With this in mind have kept
highs in the upper 80s and around 90 rather than the middle 80s.
There are signs of increasing cold air advection by Wednesday as
the upper closed low moves east of the forecast area. With this in
mind, have shown a little more of a cool down for the later part
of the forecast.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1224 PM CDT THU JUN 9 2016
Gusty winds will be the main feature of the afternoon, with gusts up
to 30 kts seen. After 00Z, southerly winds will die down staying
below 10kts through the night. There looks to be another chance
for LLWS tonight at all sites, but values to meet this criteria
look marginal at the moment so have opted to leave it out of this
TAF issuance. Tomorrow after 16Z, gusty winds return.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Wolters
AVIATION...Heller
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
947 PM CDT FRI JUN 10 2016
.UPDATE...
Issued at 947 PM CDT Fri Jun 10 2016
Once again, only minor changes were made to the overnight forecast
with this update cycle. Extrapolating upstream storms entering the
northeast part of MT as of 0245 UTC still brings the leading cells
into ND after 05 UTC, consistent with our hourly PoP forecasts. We
earlier added the possibility of a strong storm to our hazardous
weather outlook tonight, and there`s a small risk of severe storms,
too. The near-storm environment upstream in northeast MT contains
strong deep-layer shear (effective bulk wind differences in excess
of 60 kt per the RAP-based/SPC mesoscale analysis) and modest CAPE
on the northern axis of a reservoir of strong instability. RAP
forecast soundings across western and central ND suggest similarly
strong deep-layer shear later tonight, but with less bouyancy. We
believe the modest (albeit increasing) MUCAPE values will tend to
keep any severe risk in check tonight.
UPDATE Issued at 657 PM CDT Fri Jun 10 2016
Only minor changes were made with this forecast update. Applying a
simple speed/time of arrival method to the thunderstorms impacting
central MT at 2345 UTC would bring them into western ND after 05
UTC, so our overnight PoP forecast is on track, and also has the
support of a 40 kt low-level jet that is expected to develop and
impinge on a mid-level frontal zone. Recent HRRR and ESRL-HRRR
simulations are more aggressive and faster bringing storms out of
MT and into ND, but both appear to be overzealous with deep
convection in south central MT compared to radar trends as of
early evening. That in turn lowers our confidence a bit in those
solutions for the time being.
&&
.SHORT TERM...(This evening through Saturday Night)
Issued at 402 PM CDT Fri Jun 10 2016
The potential for severe weather late Saturday afternoon
into Saturday night highlights the short term.
The latest model package (GFS20/ECMWF/SREF/Canadian) project quasi-
zonal flow aloft transitioning into southwest flow through Saturday,
as an upper level trough pushes inward from the Pacific NW.
Meanwhile, at the surface, low pressure will deepen over the
southeast Montana/northeast Wyoming corner, moving northeastward
through Saturday. Sufficient instability coupled with favorable 0-6
Km agl bulk shear of around 40 kts and dewpoints near 60F, will aid
in thunderstorm development. Models are also in fairly good
agreement with painting a band of CAPE between 5500 and 4000 joules
in west central and south central areas.
The current SPC convective outlook places much of western and
central ND in a slight risk for severe thunderstorms Saturday, with
a highlighted area for an enhanced risk over the west, late Saturday
afternoon into Saturday night. The main threats will be very large
hail, damaging winds, with a few tornadoes possible.
Supporting the probability for tornadoes are the 12Z NAM forecast
soundings in the southwest, which are projecting strong 0-1 km
storm relative helicity over 200 m2/s2 for Saturday evening. The
soundings also show low lcl heights around 1200 m agl for Saturday
evening.
.LONG TERM...(Sunday through Friday)
Issued at 402 PM CDT Fri Jun 10 2016
Seasonable temperatures along with chances for thunderstorms
continuing into Wednesday, highlights the long term.
Southwest flow, with embedded shortwaves, will keep a chance of
thunderstorms in the forecast in many areas through the middle of
next week. The latest deterministic and ensemble models suggest mid-
level flow may amplify again with ridging becoming more prevalent by
late next week, leading to a drier period, at least temporarily.
Highs will generally be in the 70s and 80s F over western and
central areas from Sunday through Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 657 PM CDT Fri Jun 10 2016
VFR conditions are generally expected to prevail tonight and on
Saturday. However, there will be a chance of thunderstorms after
about 05 UTC in western ND, spreading into central ND in the 08
to 14 UTC time frame and lingering through Saturday. Confidence
in storms impacting specific terminals is modest though, so the 00
UTC TAFs only included a VCTS at KISN and KMOT tonight and early
Saturday based on upstream radar trends. Much more intense and
severe storms may develop over western ND after 21 UTC Saturday.
&&
.BIS Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...AC
LONG TERM...AC
AVIATION...CJS
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
657 PM CDT FRI JUN 10 2016
.UPDATE...
Issued at 657 PM CDT Fri Jun 10 2016
Only minor changes were made with this forecast update. Applying a
simple speed/time of arrival method to the thunderstorms impacting
central MT at 2345 UTC would bring them into western ND after 05
UTC, so our overnight PoP forecast is on track, and also has the
support of a 40 kt low-level jet that is expected to develop and
impinge on a mid-level frontal zone. Recent HRRR and ESRL-HRRR
simulations are more aggressive and faster bringing storms out of
MT and into ND, but both appear to be overzealous with deep
convection in south central MT compared to radar trends as of
early evening. That in turn lowers our confidence a bit in those
solutions for the time being.
&&
.SHORT TERM...(This evening through Saturday Night)
Issued at 402 PM CDT Fri Jun 10 2016
The potential for severe weather late Saturday afternoon
into Saturday night highlights the short term.
The latest model package (GFS20/ECMWF/SREF/Canadian) project quasi-
zonal flow aloft transitioning into southwest flow through Saturday,
as an upper level trough pushes inward from the Pacific NW.
Meanwhile, at the surface, low pressure will deepen over the
southeast Montana/northeast Wyoming corner, moving northeastward
through Saturday. Sufficient instability coupled with favorable 0-6
Km agl bulk shear of around 40 kts and dewpoints near 60F, will aid
in thunderstorm development. Models are also in fairly good
agreement with painting a band of CAPE between 5500 and 4000 joules
in west central and south central areas.
The current SPC convective outlook places much of western and
central ND in a slight risk for severe thunderstorms Saturday, with
a highlighted area for an enhanced risk over the west, late Saturday
afternoon into Saturday night. The main threats will be very large
hail, damaging winds, with a few tornadoes possible.
Supporting the probability for tornadoes are the 12Z NAM forecast
soundings in the southwest, which are projecting strong 0-1 km
storm relative helicity over 200 m2/s2 for Saturday evening. The
soundings also show low lcl heights around 1200 m agl for Saturday
evening.
.LONG TERM...(Sunday through Friday)
Issued at 402 PM CDT Fri Jun 10 2016
Seasonable temperatures along with chances for thunderstorms
continuing into Wednesday, highlights the long term.
Southwest flow, with embedded shortwaves, will keep a chance of
thunderstorms in the forecast in many areas through the middle of
next week. The latest deterministic and ensemble models suggest mid-
level flow may amplify again with ridging becoming more prevalent by
late next week, leading to a drier period, at least temporarily.
Highs will generally be in the 70s and 80s F over western and
central areas from Sunday through Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 657 PM CDT Fri Jun 10 2016
VFR conditions are generally expected to prevail tonight and on
Saturday. However, there will be a chance of thunderstorms after
about 05 UTC in western ND, spreading into central ND in the 08
to 14 UTC time frame and lingering through Saturday. Confidence
in storms impacting specific terminals is modest though, so the 00
UTC TAFs only included a VCTS at KISN and KMOT tonight and early
Saturday based on upstream radar trends. Much more intense and
severe storms may develop over western ND after 21 UTC Saturday.
&&
.BIS Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...AC
LONG TERM...AC
AVIATION...CJS
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
604 PM CDT THU JUN 9 2016
.UPDATE...
Issued at 604 PM CDT Thu Jun 9 2016
Only minor changes were made to the forecast with this update. We
did spread the chance of thunderstorms eastward a bit more quickly
than earlier advertised given radar trends. The severe storms that
moved out of northwest and into north central ND are still within
an axis of MLCAPE of 2000+ J/kg given surface temperatures in the
90s and dewpoints in the lower 60s F in their inflow region. Very
recent radar trends have shown a decreasing trend to those storms,
though, which is likely because they are outpacing the stronger
deep-layer shear that exists further west. That may marginalize
the severe threat with the batch of storms northwest of Minot as
of 23 UTC. Meanwhile, convection in southwest ND is high-based in
an environment characterized by 40+ F temperature-dewpoint spreads
and weak shear as of late afternoon, so we only expect a gusty
wind threat with that activity for the next few hours.
We are watching storms in MT closely (including one particularly
long-lived supercell approaching Jordan as as of 23 UTC). Simple
extrapolation of that activity brings it to the ND border by mid
evening. If it reaches ND before the boundary layer is able to
cool sufficiently for increasing capping to take hold, then there
could be a more organized severe threat, particularly over west
central and northwest ND.
&&
.SHORT TERM...(This evening through Friday)
Issued at 205 PM CDT Thu Jun 9 2016
The expectation of severe thunderstorms west through north central
this evening and tonight highlights the short term period.
Latest water vapor imagery shows an upper low circulating just off
of Vancouver Island with a downstream southwest flow into North
Dakota. Shortwaves peeling off from the main low and through the
northern Rockies continue to produce thunderstorms in central
Montana. The upper level low will meander and head into Washington
state Friday before ejecting northeast through southern Canada
over the weekend. This slow movement and trajectory keeps western
and central ND in a favored area for periodic thunderstorms.
The next shortwave to affect western and central ND is seen over
western Montana into central Idaho. An associated surface cold
front will advance from southern and eastern Montana into North
Dakota tonight. Nsharp soundings continue to show high based
thunderstorms around 8kft to 10kft west and north central with
the primary threat of damaging winds. Dewpoints have been dropping
across the west as mixing aloft with drier air ensues. Beach for
example went from a 61f dewpoint to 48f dewpoint. Mixed layer cape
should be decreasing as a result. Dcape values of around 1500 j/kg
across the west late this afternoon and evening indicative of
strong downdraft/damaging wind potential.
Lcl heights will likely be a bit lower across north central ND as
Minot sounding shows dewpoints in the lower 60s holding on through
the evening. May see cloud bases around 5kft with an increased
depth in cape values. The combination of surface-1km shear of
around 25kt, sfc-1km and sfc-3km relative helicity of 189 and
223 meters squared/second squared may provide a brief window of
tornado opportunity. The latest HRRR composite reflectivity shows
the strongest cells moving across north central between 03z-06z
which is coincident with the forecast sounding parameters mentioned
above. Thus, damaging winds, large hail, and a possible tornado
will be monitored north central early tonight. Convection will
taper off from west to east after midnight.
.LONG TERM...(Friday night through Thursday)
Issued at 205 PM CDT Thu Jun 9 2016
Brief transitory ridging occurs Friday after the passage of
Thursday nights shortwave. Thus dry during the daylight hours
Friday. Another round of thunderstorms expected Friday night into
Saturday, with a second shortwave following for Saturday
evening/night. It appears that on Sunday, thunderstorms should be
confined from the Turtle Mountains south into the James River
Valley. Severe thunderstorms possible with each round, but severe
weather is more favored Saturday evening/night along and ahead of
a well defined warm front draped over most of western and central
North Dakota. SPC maintains a large slight risk area.
Continued southwest flow through the middle of next week with
signs of another building ridge across central ND which may
gradually decrease chances for precipitation later in the week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 604 PM CDT Thu Jun 9 2016
Thunderstorms initially over western and north central ND as of 23
UTC will slowly move eastward this evening, while additional cells
move out of MT and into western ND by mid to late evening. Showers
and thunderstorms will then move across western and central ND in
the 03 to 09 UTC time range. Local MVFR and IFR conditions and
gusty winds are expected with thunderstorms, and some could be
severe with large hail and damaging winds.
&&
.BIS Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...KS
AVIATION...CJS
Area Forecast Discussion
National Weather Service Tucson AZ
234 AM MST SAT JUN 11 2016
.SYNOPSIS...Drier air starts to work in from the west today
pushing the best chance of storms to areas east of Tucson. A few
thunderstorms may occur near the New Mexico border on Sunday. Dry
conditions will prevail next week with a drier air mass over the
area. Daytime temperatures will remain near normal or a few degrees
below normal through Tuesday, then hotter temperatures return next
Wednesday and Thursday.
&&
.DISCUSSION...Radar was quiet across SE Arizona as of 2 am. However
S of Douglas there were isolated showers associated with a decaying
complex. Wouldn`t be surprised if a weak MCV comes out of this
complex and pushes north along the AZ/NM border later this morning.
Precipitable water values remain well above mid-June normals this
morning with values mostly in the 1.00"-1.50" range. Water vapor
imagery showed an upper level low approaching southern CA. Drier air
will start to push in from the west as the day progresses, but
enough will be around across the eastern 2/3rds of the area for
isolated valley/scattered mountains showers and thunderstorms.
Precipitable water values are forecast to be below 1" on Sunday with
a slight chance of storms relegated to the White mountains. High
temperatures this weekend will remain several degrees below normal.
Upper level trof will push across the state on Monday providing
slightly cooler daytime temperatures and further drying of the
atmosphere.
Upper ridge strengthens over the area Tuesday through Friday
resulting in warmer daytime high temperatures.
Outside of this forecast package are likely HOTTER daytime
temperatures as the upper ridge continues to strengthen over the
area. Highs next weekend could rival what occurred earlier this
month. Stay tuned.
&&
.AVIATION...VALID THRU 12/12Z.
KTUS E, few-sct 10-15kft bkn-ovc 20-25kft MSL, isold-wdly sct
-SHRA/-TSRA. W KTUS, skc-sct 12-15kft MSL.
Surface wind mainly less than 10 kts except near thunderstorms.
Aviation discussion not updated for TAF ammendments.
&&
.FIRE WEATHER...Isolated to scattered showers and thunderstorms
again today. A few thunderstorms Sunday will likely be limited to
the higher terrain east of Tucson. Thunderstorm outflows will
occasionally produce brief strong, gusty and erratic winds. Dry
conditions will then prevail area-wide Monday through Friday of next
week. Daytime temperatures will be a few degrees below normal into
early next week, then hotter temperatures return Wednesday into next
Friday.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
[top]
Area Forecast Discussion
National Weather Service Phoenix AZ
230 AM MST SAT JUN 11 2016
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
As the larger synoptic scale ridge axis shifts into the southern
plains early this morning, several shortwaves/vorticity centers are
evident in satellite imagery streaming north on the western
periphery of this high pressure. The primary vorticity
center/easterly wave has already lifted near Las Vegas, however
several convectively induced MCV`s are still evident over NE AZ and
SE AZ within the debris cloud field. Meanwhile, a fuller latitude
trough in the westerly flow across the East Pacific was edging
towards the US West Coast, and effectively enveloping the local
forecast area under dryslot subsidence. This latter East Pacific
trough will slowly move across the SW Conus through early next week
and be the primary influence on weather and temperatures.
Through today, flow aloft will become more predominantly southwest
gradually scouring away moisture through horizontal advection and
vertical mixing. 00Z KTWC sounding data still sampled a daily record
1.49" PWAT, however 00Z KNKX data interrogated substantial drying in
the H8-H5 layer which will undoubtedly overspread the downstream
area (i.e. SE CA and AZ) through today. NAM Bufr forecast soundings
are still reluctant to fully relinquish the 10 g/kg boundary layer
moisture profiles in lower elevation locations this afternoon
resulting in a period of modest instability in a weakly capped
environment. Given trends in satellite and past events under similar
flow patterns, believe upslope regions over the Mogollon Rim and
White Mountains would be more favored for deep convection; and a
vast majority of high resolution models and ensemble systems support
this rational.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Isolated weak thunderstorms will nibble at the fringes of metro
Phoenix through 06Z but are not expected to reach any of the
terminals. However, weakening outflow from distant storms will lead
to development of easterly surface winds overspreading east Valley
beginning 05Z. May see a stray sprinkle/shower through 07Z but
otherwise debris clouds will thin out overnight. Anticipate
redevelopment of some thunderstorms over higher terrain east of
Phoenix after 18Z.
Southeast California/Southwest Arizona including KIPL and KBLH:
Upper level disturbance will exit southeast California overnight
leaving behind clearing skies. Before then, some isolated weak
showers will linger over/near Joshua Tree National Park through 08Z.
Surface winds will continue to favor south and southeasterly
directions but will be relatively light overnight before
strengthening during the afternoon (gusts to 20-30 kts).
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday...
As high pressure begins to build back over the region, dry air will
predominate with near normal temperatures Monday through Tuesday.
Warmer than average temperatures will arrive Wednesday and continue
for the remainder of the week. Minimum humidities in the upper
single digits to mid teens Monday will fall into the mid single
digit to low teen range by Thursday and Friday with fair overnight
recovery. Winds will remain mainly on the light side with afternoon
gustiness through the forecast period, following typical diurnal
trends.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...MO
AVIATION...AJ
FIRE WEATHER...Hernandez/Percha
[top]
Area Forecast Discussion
National Weather Service Flagstaff AZ
955 PM MST FRI JUN 10 2016
.SYNOPSIS...Expect numerous showers and thunderstorms over central
and western Arizona to slowly end overnight. Drier southwest flow
returns later on Saturday and Sunday, with breezy conditions and far
less shower activity. A chance of showers and thunderstorms returns
on Monday, before a strong warming and drying trend for the
remainder of next week.
&&
.DISCUSSION...A large area of convection formed this evening along
with eastern border of a mesoscale upper low moving north through
the Lower Colorado River Basin. This area is moving northwest and
propagating outflow boundaries to the west. Much higher PW air is
associated with this area of rainfall, with dewpoints over 50 in
many places. Many areas have reported up to an inch of rainfall.
The hardest hit locations are in northern Gila county and into
southern Coconino county.
As the upper low moves away from the area later tonight, the forcing
will weaken and drier southwest will replace the current airmass by
later Saturday and Sunday.
An upper level trough moving through the area will continue breezy
to windy conditions through the weekend. Enough cold air aloft may
accompany the trough passage by Monday for the formation of more
thunderstorms, albeit from a different mechanism and a different
moisture source.
The rest of next week will be hot and dry.
We have been updating most of the shift as we track this area of
convection, trends should be downward from here on out. No further
significant updates are anticipated.
&&
.AVIATION...For the 06Z Package...SCT SHRA/TSRA with isolated
MVFR +TSRA VRB30G40kts moving northwest at 15-20kts through
10Z...then Isold -shra/-tsra. Aviation discussion not updated for
TAF amendments.
&&
.FIRE WEATHER...Expect increasing high-based shower and thunderstorm
activity from southeast to northwest through the overnight hours.
Strong and erratic outflow winds are likely near storms. On
Saturday, lingering moisture will cause a round of scattered high-
based storms, primarily over higher terrain. Gusty southwest winds
and mainly dry conditions are expected on Sunday.
Monday through Wednesday...Slight chances for thunderstorms are
forecast Monday. Dry weather and a warming trend forecast Tuesday
and Wednesday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...Peterson
AVIATION...MAS
FIRE WEATHER...RR
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Phoenix AZ
954 PM MST FRI JUN 10 2016
.UPDATE...
Updated Aviation section.
&&
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather than the past week. A
temporary increase in moisture will support some showers and storms
over higher terrain of central and southern Arizona overnight and
Saturday. Temperatures near the seasonal average will continue
through early next week before hotter conditions become re-
established during the latter half of the week.
&&
.DISCUSSION...
Vort max centered over southeast CA this evening continues to track
northward. Despite the vorticity advection, only isolated weak
showers developed over southwest AZ and southeast CA earlier this
afternoon due to insufficient surface heating to break the CIN. Best
storm activity was over east-central and southeast AZ where CAPE was
better and CIN was breakable. Still ongoing activity as of this
writing over northern Gila and far northeast Maricopa County.
However, considerable CIN has kept storms out of most of the metro
area so far and that will likely be the case the rest of the night.
Held on to a low end slight chance over the lower elevations of
Maricopa County and Pinal County due to lingering CAPE and activity
over northern AZ (plus outflow from southern Gila Co.) Otherwise,
dropped PoPs elsewhere except over/near Joshua Tree National Park
close to the vort max center and where there have been lingering
echoes. Models show the vort max and convection to the east tracking
northward overnight. The dropoff in the model convection makes sense
given a southerly component to the steering flow and the fact that
things are quiet over southeast AZ. Held on to PoPs over zone 24 for
Saturday per model CAPE. Of note, both RAP and NAM12 have a batch of
CAPE that affects metro Phoenix but CIN values are a bit high.
&&
.Previous Discussion...issued 159 pm MST/PDT...
A brief introduction to the monsoon is expected this afternoon and
this evening across the desert southwest. Latest 12z sounding from
TWC sampled a record PWAT of 1.46 inches, while SPC mesoanalysis
indicates that even higher PWATS are concentrated across southern
Pima County associated with a well- defined vort max and 700 mb
inverted trough across northern Sonora.
Widespread canopy of high clouds from this low overspread much of
southern Arizona this morning. However, clouds have dissipated as
expected across eastern Arizona and congested CU has been quick to
develop across the higher terrain of southeastern AZ. Surface
dewpoints remain exceptionally high this afternoon across the lower
deserts, generally in the mid to upper 50s and have even increased
early this afternoon. Latest ACARS soundings out of KPHX show an
exceptionally moist profile with mixing ratios exceeding 10g/kg
through 750 mb. However, a strong subsidence inversion is also
evident, which will initially act to inhibit convection across the
Phoenix area. SPC mesoanalysis depicts MLCAPEs in excess of 1000 J/kg
across SE AZ, while the aforementioned CIN is strong and prevalent
from Phoenix northwestward through the lower Colorado River.
Southeasterly steering flow around 25 kt between the Four Corners
anticyclone and the inverted trough is also quite anomalous. General
consensus among the latest CAMs is that increasing instability and
convection across SE AZ will propagate northwestward, possibly
reaching eastern portions of the Phoenix area this evening. PoPs in
the latest raw and post-processed guidance have trended upward and
the forecast was adjusted accordingly, as high as 30 to 40 percent
across portions of Pinal and southern Gila counties. Typical
inverted-V soundings suggests a high probability of strong
downdrafts. There also remains a discernible threat for outflow
boundaries producing blowing dust and the Blowing Dust Advisory
remains in effect for Pinal and southern Maricopa counties through
this evening. Models remain in good agreement that the activity will
lift northward into northern AZ later this evening.
By Saturday, flow aloft becomes much stronger from the southwest
helping remove any convective debris, but also shearing any small
shortwaves and/or more pronounced divergence fields well away from
the forecast area. The deeper southwest flow will also aid in
mechanically removing moisture from the atmospheric column, though
NAM Bufr soundings strangely still show 10 g/kg and a weakly capped
environment Saturday afternoon. Feel better mixed GFS Bufr output
closer to 6 g/kg may be more accurate forcing most (if not all)
deeper convection in an upslope regime along the Rim and White
mountains. This stronger flow regime will also restrict the ability
of any outflow boundaries from traveling appreciably far from their
origination point.
Forecast models during the first half of next week remain in good
agreement that modest cold core troughing will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range. By
this time, any better quality moisture will have been repositioned
downstream of southeast California and Arizona and all evidence
points to dry weather (sans high terrain locations of eastern AZ).
However, the benefit will be temperatures in a near normal range
with highs in the upper 90s to lower 100s. Unfortunately as this
trough continues to propagate east, ridging will rebuild into the
area with H5 heights rebounding to a 588-594dm range yielding
afternoon highs back near 110F by the end of the week.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Isolated weak thunderstorms will nibble at the fringes of metro
Phoenix through 06Z but are not expected to reach any of the
terminals. However, weakening outflow from distant storms will lead
to development of easterly surface winds overspreading east Valley
beginning 05Z. May see a stray sprinkle/shower through 07Z but
otherwise debris clouds will thin out overnight. Anticipate
redevelopment of some thunderstorms over higher terrain east of
Phoenix after 18Z.
Southeast California/Southwest Arizona including KIPL and KBLH:
Upper level disturbance will exit southeast California overnight
leaving behind clearing skies. Before then, some isolated weak
showers will linger over/near Joshua Tree National Park through 08Z.
Surface winds will continue to favor south and sotheasterly
directions but will be relatively light overnight before
strengthening during the afternoon (gusts to 20-30 kts).
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday... As high pressure begins to build back over
the region, dry air will predominate with near normal temperatures
Monday through Tuesday. Warmer than average temperatures will arrive
Wednesday and continue for the remainder of the week. Minimum
humidities in the upper single digits to mid teens Monday will fall
into the mid single digit to low teen range by Thursday and Friday
with fair overnight recovery. Winds will remain mainly on the light
side with afternoon gustiness through the forecast period, following
typical diurnal trends.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...AJ
PREVIOUS DISCUSSION...Hirsch/MO
AVIATION...AJ
FIRE WEATHER...Hernandez/Percha
AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
1121 PM PDT FRI JUN 10 2016
.SYNOPSIS...
A low pressure system will bring a slight chance of showers and
thunderstorms mainly in the mountains into Sunday. Elsewhere the
onshore flow will bring clouds...fog and drizzle into Sunday. Next
week...a warming trend will occur with fair skies inland and an
overnight coastal marine layer...clearing to the beaches by the
afternoon.
&&
.SHORT TERM...(FRI-MON)
A weak upper level low pressure system several hundred miles
southwest of the forecast area will contine to drift northeast
into our coastal waters by Saturday afternoon. This system is
pulling up quite a bit of mid and high level clouds across the
region this evening, with some low clouds beginning to return
along the coast. A weak inverted trough with associated vorticity
lobe has also brought a considerable amount of mid and high level
clouds with some light showers over deserts of southeast
California this evening
One feature to watch tonight will be an embedded vorticity lobe
across the inner coastal waters tracking norhtward towards Ventura
and SBA counties. With some upper level difflunece, mid level
moisture, and elevated CAPE above 600 mb level, there is a very
slight chance of elevated convection with this feature (only about
10 percent probability). Would not be surprised to see a few
sprinkles tonight at the very least fall with this band of mid
level clouds. Otherwise fairly strong catalina eddy circulation
will spin up tonight, likely lifting the marine layer depth to
around 2500 feet by Saturday morning. Not sure how organized the
low clouds will be tonight due to the influx of mid and higher
level clouds, but should see low clouds fill in across many
coastal/valley areas tonight into Saturday morning, with many
coastal areas south of Point Conception remaining mostly cloudy in
the afternoon. Will also add some patchy drizzle for later tonight
into Saturday morning due to the lifting marine layer and light
southeast wind flow through the boundary layer. Even better chance
of drizzle for Saturday night/Sunday morning.
The proximity of the upper low will help to destabilie the
atmosphere over interior sections this weekend as colder air aloft
moves into the region. Model soundings showing marginal moisture
for tomorrow afternoon, but will keep slight chance of
afternoon showers/tstms going for mountains of SBA/Ventura county
mountains.
*** From previous discussion ***
The 12Z NAM was indicating some decent instability developing Sat
and Sun afternoons over the higher mtns of VTU/SBA Counties (LI
around -4 to -5 and CAPE around 600 to 800 J/kg) but moisture is
pretty limited. Even so, the presence of the upper trof/upper low
may be enough to set off an isolated afternoon and early evening
thunderstorm in this area each day. The chances of any thunderstorm
development is around 15 percent at best, so low confidence overall
in this scenario with a minimal slight chance.
As far as temps go, a cooling trend can be expected Sat and Sun,
with highs about 3 to 10 deg below normal for many areas by Sat,
then cool further to about 4 to 12 deg for Sun. Highs by Sun will
range from the 60s to lower 70s along the coast, and 70s to lower
80s in the valleys and foothills except mid to upper 80s in the
Antelope Valley. For Mon, temps will warm slightly but remain 2 to
11 deg below normal for many areas.
.LONG TERM...(TUE-FRI)
The GFS and EC are in generally good agreement thru the extended
period. A weak upper ridge can be expected Tue. A broad sw flow
aloft can then be expected over srn CA for Wed thru Fri as the area
will be between an upper level ridge over the Rockies and a large
upper trof over the ern Pac.
The marine layer pattern will continue Tue and Wed with varying
amounts of low clouds and fog expected for the coast and vlys. It
looks like the extent of the low clouds may diminish some for Thu
and Fri with generally the L.A. County coast prone to the low clouds
night and morning hours. Otherwise, skies will be mostly clear Tue
thru Fri. Typical June onshore flow will continue afternoon and
evening hours. There may also be some weak offshore flow night and
morning hours Thu and Fri for SLO/SBA Counties. Temps will continue
to be several degrees below normal for many areas Tue and Wed, then
warm to slightly below normal to near normal Thu, and near normal to
several degrees above normal for Fri. The warmest day overall during
the extended period will be Fri with highs in the warmest vlys and
foothills reaching the mid 80s to low 90s, except mid to upper 90s
in the Antelope Vly.
&&
.AVIATION...11/0600Z.
At 05Z, the marine layer depth at KLAX was around 1350 feet deep.
The inversion top was around 5500feet with a temperature of 19
degrees Celsius.
North of Point Conception...There is a chance of LIFR to IFR
conditions, mainly between 08Z and 16Z. Otherwise, VFR conditions
will prevail through at least 03Z.
South of Point Conception...Low to moderate confidence in the
current forecast. MVFR conditions are expected to spread into all
coastal and valley terminals by 10Z, or 13Z at the latest. MVFR
will likely linger across coastal and valley terminals throughout
the period. There is a chance of IFR conditions in any
drizzle/showers.
KLAX...MVFR conditions will likely linger throughout the period.
There is a 40 percent chance of VFR conditions between 19Z and
01Z. There is a 20 percent chance of IFR conditions in any
drizzle/showers. Southeast winds greater than 7 knots will
continue through 15Z. South winds greater than 10 knots are
possible between 15Z and 19Z.
KBUR...MVFR conditions will spread into KBUR by 10Z and likely
linger throughout the period. There is a 40 percent chance of VFR
conditions between 19Z and 01Z. There is a 20 percent chance of
IFR conditions in any drizzle/showers.
&&
.MARINE...10/800 PM.
Gale warnings remain in effect tonight for zones 670 and 673.
Small craft advisory conditions are then not expected Saturday
night through Monday morning. Northwest locally generated seas
will build to around 10 feet from Piedras Blancas to San Nicolas
island tonight and then subside below 10 feet Saturday night and
build to around 10 feet Tuesday. Otherwise an active storm track
over the Southern Ocean last weekend through midweek had generated
seas within 190-220 degrees relative to Ventura. The long period
swells will build through next week. Small craft advisory for
hazardous sea conditions area not expected but extra currents and
surging along exposed south facing shores are likely. A catalina
eddy circulation will bring s to e winds of 10 to 15 knots across
the inner waters at times tonight through Sunday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 5 AM PDT Saturday For
zone 645. (See LAXMWWLOX).
Gale Warning in effect until 5 AM PDT Saturday For zones
670-673. (See LAXMWWLOX).
Small Craft Advisory in effect until 9 AM PDT Saturday For
zone 676. (See LAXMWWLOX).
&&
$$
PUBLIC...Gomberg/Sirard
AVIATION...Hall
MARINE...Gomberg
SYNOPSIS...Seto/Hall
weather.gov/losangeles
[top]
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1041 PM PDT FRI JUN 10 2016
.SYNOPSIS...Warmer weather is forecast this weekend, particularly
across the northern portion of the region, as onshore winds
weaken and drier air filters into the area. A cooling trend will
then occur during the first half of next week as another upper
level trough sets up along the West Coast.
&&
.DISCUSSION...As of 8:50 PM PDT Friday...A strong surface high
building offshore produced brisk northwest winds across our region
today which helped mix out the marine layer. The result was a
mostly sunny day across our region with occasional high clouds.
High temperatures today were slightly warmer than on Thursday and
close to seasonal norms.
High pressure offshore is forecast to build inland across Oregon
and far northern California tonight. North-to-south surface
pressure gradients are already increasing with the ACV-SFO
gradient up to 6.8 mb as of 8 pm. As high pressure continues to
build inland to our north overnight, northerly winds will increase
in the hills, mainly across the North Bay. Elevations above 1000
feet in the North Bay mountains will likely see local wind gusts
up to 35 mph by late tonight, with the strongest winds expected in
the hills of Napa County and eastern Sonoma County. Along with
these increasing winds will come lowering relative humidity
values as much drier air sweeps in from the north. The combination
of gusty winds and low relative humidity will result in increased
fire danger in the North Bay Mountains starting late tonight and
continuing through midday Sunday (see fire weather section below).
The developing dry northerly flow will result in warmer weather on
Saturday, particularly across the SF Bay Area where highs are
expected to be up to 10 degrees warmer than today. Brisk northerly
flow will mostly be confined to the northern portion of our
forecast area so areas from Monterey Bay southward will see less
robust warming tomorrow, probably no more than about five
degrees.
Northerly flow is forecast to rapidly decrease during the day
Sunday which will allow marine air to move inland more easily by
afternoon. Thus, cooling will begin on Sunday, but mostly near
the coast. Inland valleys and the hills will remain warm through
the end of the weekend.
A widespread cooling trend is forecast from Monday through the
middle of next week as an upper trough gradually deepens just off
the West Coast. Temperatures by the middle of next week are
forecast to be anywhere from 5 to 15 degrees cooler than normal.
Marine layer clouds will probably become more widespread and
persistent by Monday, but then may mix out by midweek based on the
amount of cooling forecast to occur aloft.
Both the GFS and ECMWF begin to increase temps late next week as
the upper trough starts to lift to the north. In any case,
temperatures are likely to remain below normal throughout next
week.
&&
.AVIATION...as of 10:41 PM PDT Friday...Surprisingly the marine
layer is beginning to reform with the Fort Ord profiler showing a
marine layer around 1600 feet deep. The San Jose State Radiometer
is also showing a subsidence inversion topping off at about 1000
feet. At this point the northerly surface pressure gradient is to
great to allow stratus to advect into the San Francisco bay area.
However, stratus is already developing along the Monterey coast.
Therefore, confidence is growing for late night stratus to impact
Monterey and Salinas terminals.
Vicinity of KSFO...VFR conditions are expected to persist over the
next 24 to 36 hours. Westerly winds have decreased to around 18 kt
and are anticipated to continue to decrease to 5 to 10 kt
overnight. With the inversion present stratus will be possible
near KOAK overnight, confidence is low so haven`t put it in the
forecast.
Confidence high for KSFO.
Confidence low to moderate for KOAK.
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...VFR conditions are being reported at the
terminals this evening. However, low clouds are forming along the
coast and are anticipated to impact the terminals overnight. These
clouds will be thin and expected to quickly burn off Saturday
morning.
Confidence moderate.
&&
.FIRE WEATHER...As of 6:55 PM PDT Friday...Surface high pressure
is forecast build inland across Oregon and far Northern California
on Friday Night. This will result in increasing northerly winds at
higher elevations by late Friday Night, particularly across the
North Bay Mountains. In addition, a much drier airmass will move
into the region by Saturday morning. Relative humidity values are
expected to drop as low as the single digits in the North Bay on
Saturday and very poor humidity recovery is expected on Saturday
Night. The combination of gusty north winds and low relative
humidity will create increased fire danger in the North Bay
Mountains by late Friday Night and Saturday Morning. A Red Flag
Warning has been issued for the North Bay Mountains starting at 5
AM PDT Saturday morning. Strongest winds are expected to be over
Napa County and Eastern Sonoma County where the higher ridges and
peaks may see wind gusts up to 35 mph. Winds are forecast to
decrease Saturday afternoon and evening, but then increase once
again Saturday night into Sunday morning. The Red Flag warning is
in effect until midday Sunday.
&&
.MARINE...as of 8:54 PM PDT Friday...A strong surface pressure
gradient will maintain gusty northerly winds across the coastal
waters tonight. Local gale force gusts will be possible...especially
south of PT. Sur. These strong winds will generate steep fresh
swell and rough sea surface conditions. Conditions will begin to
improve Saturday as the surface pressure gradient weakens.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tngt...SCA...Mry Bay until 3 AM
SCA...Pigeon Pt to Pt Pinos 0-10 nm until 3 AM
SCA...Pt Arena to Pt Reyes 0-10 nm
SCA...Pt Arena to Pigeon Pt 10-60 nm
SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm
SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm from 2 AM
GLW...Pt Pinos to Pt Piedras Blancas 0-10 nm until 2 AM
SCA...Pt Reyes to Pigeon Pt 0-10 nm
&&
$$
PUBLIC FORECAST: Dykema
AVIATION: Larry
MARINE: Larry
FIRE WEATHER: Dykema
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www.Facebook.com/nwsbayarea
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Area Forecast Discussion
National Weather Service Phoenix AZ
954 PM MST FRI JUN 10 2016
.UPDATE...
Updated Aviation section.
&&
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather than the past week. A
temporary increase in moisture will support some showers and storms
over higher terrain of central and southern Arizona overnight and
Saturday. Temperatures near the seasonal average will continue
through early next week before hotter conditions become re-
established during the latter half of the week.
&&
.DISCUSSION...
Vort max centered over southeast CA this evening continues to track
northward. Despite the vorticity advection, only isolated weak
showers developed over southwest AZ and southeast CA earlier this
afternoon due to insufficient surface heating to break the CIN. Best
storm activity was over east-central and southeast AZ where CAPE was
better and CIN was breakable. Still ongoing activity as of this
writing over northern Gila and far northeast Maricopa County.
However, considerable CIN has kept storms out of most of the metro
area so far and that will likely be the case the rest of the night.
Held on to a low end slight chance over the lower elevations of
Maricopa County and Pinal County due to lingering CAPE and activity
over northern AZ (plus outflow from southern Gila Co.) Otherwise,
dropped PoPs elsewhere except over/near Joshua Tree National Park
close to the vort max center and where there have been lingering
echoes. Models show the vort max and convection to the east tracking
northward overnight. The dropoff in the model convection makes sense
given a southerly component to the steering flow and the fact that
things are quiet over southeast AZ. Held on to PoPs over zone 24 for
Saturday per model CAPE. Of note, both RAP and NAM12 have a batch of
CAPE that affects metro Phoenix but CIN values are a bit high.
&&
.Previous Discussion...issued 159 pm MST/PDT...
A brief introduction to the monsoon is expected this afternoon and
this evening across the desert southwest. Latest 12z sounding from
TWC sampled a record PWAT of 1.46 inches, while SPC mesoanalysis
indicates that even higher PWATS are concentrated across southern
Pima County associated with a well- defined vort max and 700 mb
inverted trough across northern Sonora.
Widespread canopy of high clouds from this low overspread much of
southern Arizona this morning. However, clouds have dissipated as
expected across eastern Arizona and congested CU has been quick to
develop across the higher terrain of southeastern AZ. Surface
dewpoints remain exceptionally high this afternoon across the lower
deserts, generally in the mid to upper 50s and have even increased
early this afternoon. Latest ACARS soundings out of KPHX show an
exceptionally moist profile with mixing ratios exceeding 10g/kg
through 750 mb. However, a strong subsidence inversion is also
evident, which will initially act to inhibit convection across the
Phoenix area. SPC mesoanalysis depicts MLCAPEs in excess of 1000 J/kg
across SE AZ, while the aforementioned CIN is strong and prevalent
from Phoenix northwestward through the lower Colorado River.
Southeasterly steering flow around 25 kt between the Four Corners
anticyclone and the inverted trough is also quite anomalous. General
consensus among the latest CAMs is that increasing instability and
convection across SE AZ will propagate northwestward, possibly
reaching eastern portions of the Phoenix area this evening. PoPs in
the latest raw and post-processed guidance have trended upward and
the forecast was adjusted accordingly, as high as 30 to 40 percent
across portions of Pinal and southern Gila counties. Typical
inverted-V soundings suggests a high probability of strong
downdrafts. There also remains a discernible threat for outflow
boundaries producing blowing dust and the Blowing Dust Advisory
remains in effect for Pinal and southern Maricopa counties through
this evening. Models remain in good agreement that the activity will
lift northward into northern AZ later this evening.
By Saturday, flow aloft becomes much stronger from the southwest
helping remove any convective debris, but also shearing any small
shortwaves and/or more pronounced divergence fields well away from
the forecast area. The deeper southwest flow will also aid in
mechanically removing moisture from the atmospheric column, though
NAM Bufr soundings strangely still show 10 g/kg and a weakly capped
environment Saturday afternoon. Feel better mixed GFS Bufr output
closer to 6 g/kg may be more accurate forcing most (if not all)
deeper convection in an upslope regime along the Rim and White
mountains. This stronger flow regime will also restrict the ability
of any outflow boundaries from traveling appreciably far from their
origination point.
Forecast models during the first half of next week remain in good
agreement that modest cold core troughing will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range. By
this time, any better quality moisture will have been repositioned
downstream of southeast California and Arizona and all evidence
points to dry weather (sans high terrain locations of eastern AZ).
However, the benefit will be temperatures in a near normal range
with highs in the upper 90s to lower 100s. Unfortunately as this
trough continues to propagate east, ridging will rebuild into the
area with H5 heights rebounding to a 588-594dm range yielding
afternoon highs back near 110F by the end of the week.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Isolated weak thunderstorms will nibble at the fringes of metro
Phoenix through 06Z but are not expected to reach any of the
terminals. However, weakening outflow from distant storms will lead
to development of easterly surface winds overspreading east Valley
beginning 05Z. May see a stray sprinkle/shower through 07Z but
otherwise debris clouds will thin out overnight. Anticipate
redevelopment of some thunderstorms over higher terrain east of
Phoenix after 18Z.
Southeast California/Southwest Arizona including KIPL and KBLH:
Upper level disturbance will exit southeast California overnight
leaving behind clearing skies. Before then, some isolated weak
showers will linger over/near Joshua Tree National Park through 08Z.
Surface winds will continue to favor south and sotheasterly
directions but will be relatively light overnight before
strengthening during the afternoon (gusts to 20-30 kts).
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday... As high pressure begins to build back over
the region, dry air will predominate with near normal temperatures
Monday through Tuesday. Warmer than average temperatures will arrive
Wednesday and continue for the remainder of the week. Minimum
humidities in the upper single digits to mid teens Monday will fall
into the mid single digit to low teen range by Thursday and Friday
with fair overnight recovery. Winds will remain mainly on the light
side with afternoon gustiness through the forecast period, following
typical diurnal trends.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...AJ
PREVIOUS DISCUSSION...Hirsch/MO
AVIATION...AJ
FIRE WEATHER...Hernandez/Percha
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
120 AM EDT SAT JUN 11 2016
.SYNOPSIS...
Issued at 656 PM EDT Fri Jun 10 2016
A warm and humid night will be in store for the region with lows
only dropping into the lower 70s. Hot and humid conditions can be
expected on Saturday with highs likely to climb into the 90s with
heat indices in many areas reaching the middle to upper 90s. The
chance for showers and thunderstorms will exist...mainly during
the afternoon and evening hours of Saturday. An isolated strong to
severe thunderstorm is possible...mainly north of route 30.
&&
.UPDATE...
Issued at 944 PM EDT Fri Jun 10 2016
Elognated line of strong and locally severe thunderstorms was currently
located from NE Iowa to southern WI and curving north into NW
Lower Michigan and maintaining itself. Recent storm reports and
latest mesoscale discussion all show a downward trend in severe
reports and what may be the start of a slow demise in the line.
that being said...a well established cold pool behind the line
has allowed it to accelerate and drop south and east much faster
than depicted by HRRR/RAP/NAM. A cooling boundary layer...increasing
inhibition and loss of shear should allow for this line to
weaken...hopefully before arriving into the far NW areas of the
forecast area near/after 6z. Minor tweaks to the grids but have
held with previous thoughts for the most part with marginal slight
chance pops far north and west.
Impacts on convective chances tomorrow may be quite interesting
depending on where the remnants of this convection lay out.
&&
.SHORT TERM...(This Evening through Saturday)
Issued at 245 PM EDT Fri Jun 10 2016
Warm front was finally mixing northeast through the forecast area
this afternoon in wake of morning MCS and departing cloud cover.
Unstable but weakly capped atmosphere is left behind with decreasing
bulk shear. Hires models trying to develop some isolated convection
over the south half of area this afternoon and drifting east this
evening. Will carry a low chance pop in the south to southeast
through early evening but expect this activity to be isolated if
it indeed develops.
Tonight should be mainly clear and dry but warm and muggy. Upstream
convective complex developing this afternoon will progress eastward
overnight and weaken. This could come close to far north late
tonight if it holds together but expect most activity to remain
north and west with some cloud debris late. Outflow from this
complex remains the wild card for Saturday and TSRA chances later in
the day ahead of main cold front. Outside of MCS blowoff...skies
should be mostly sunny leading to a very warm and humid day. Highs
will reach lower 90s in the west with a run at mid 90s if we see
full sun through the day. Sfc dew points likely pooling into the
upper 60s...possibly lower 70s where this mornings MCS tracked. Heat
indices could approach advisory level in the west with low 100s not
out of question. This warming coupled with modest mid level lapse
rates will lead to mixed layer CAPE approaching 2500-3000 j/kg. Deep
layer shear initially lacking until main cold front approaches in
the evening. 0-6km only around 15-20 knots during the day but Pre-
frontal trough could develop some convection in this unstable
environment. Main cold front to move through late evening into
overnight and we could see line of convection develop in Michigan
early evening and come south ahead of the front. Isolated severe
remains possible as shear increases to 25 knots but afternoon
convective development will play role in later development.
&&
.LONG TERM...(Saturday Night through Friday)
Issued at 245 PM EDT Fri Jun 10 2016
Cold front will be pushing south of area early Sunday. Could be a
lingering shower or thunderstorm early Sunday but plan on leaving
forecast dry for now with details evolving with Saturday evening
convection. Broad plains mid level ridge to build east Sunday and
with surface high over Lake Michigan we should see a mild and dry
day. Ridge begins to flatten Monday with short wave energy riding
over top. Pcpn chances will increase Monday with weak short wave
and associated weak cold front dropping in.
Forecast details become uncertain next week as strong upper low
develops and undercuts plains ridge in a rex block pattern. This
will lead to a warm front that will become quasi stationary for much
of the week over the Ohio or Wabash Valley. Precipitation chances
will exist through the week near and north of this boundary with
short waves emanating from upper low. This low will then slide
southeast toward our area mid to late week keeping pcpn chances in
forecast. Much uncertainty exists with details of this low and its
track and timing into the region. Could be some locally heavy
rainfall just to east of low track given slow movement and possible
training. Temps will be near or slightly above normal but
guidance may be on high side toward end of period as upper low
nears with rain/cloud potential.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 119 AM EDT Sat Jun 11 2016
Outflw induced density current aligned fm cntrl lwr
MI swwd into ern IA surging south this morning as parent line of
convn conts to rapidly diminish. Xpc a contd decelerating trend
w/time esp w/ewd extent and suspect it will stall out inbtwn the
terminals ltr this morning. That said...this ftr likely to initiate
new convn by erly aftn as warm sector w/swd extent this am remains
cld free and will destabilized rapidly through the morning. Thus vfr
conds until then w/potential for mvfr based restrictions in +tsra
shld storms indeed dvlp this aftn...most likely invof KFWA terminal.
CAMs solutions scope attm hwvr remains uncertain w/svrl different
scenarios implied and will await swd progression/stall of outflw bfr
making an attempt if at all in psbl mention w/12Z fcst.
Otrws rapidly deepening mixed lyr into this aftn shld again yield
sfc gusts to 20kts fm lt morning through mid aftn.
&&
.IWX Watches/Warnings/Advisories...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...Fisher
SYNOPSIS...Fisher
SHORT TERM...Lashley
LONG TERM...Lashley
AVIATION...T
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Area Forecast Discussion
National Weather Service Indianapolis IN
1241 AM EDT SAT JUN 11 2016
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 217 PM EDT Fri Jun 10 2016
Hot summer weather is expected this weekend as strong high
pressure over the southeastern states pushes warm and moist air
into central Indiana on southwesterly winds.
A cold front will push throughout northeastern United States on
Saturday night...bringing a glancing blow of cooler air to
Central Indiana for Sunday. The front is not expected to result in
precipitation across Central Indiana.
Thunderstorm and precipitation chances will increase next work
week as several upper weather level disturbances are expected to
move our way.
&&
.NEAR TERM /Early This Morning/...
Issued at 1220 AM EDT Sat Jun 11 2016
Have slowed the fall in temperatures and dewpoints through daybreak
as southwest flow has been maintaining dewpoints and temps slightly
higher than expected.
Thus far outflow boundary in northern Illinois from decaying
Wisconsin convection has yet to fire any new development.
Anticipate any precipitation that does develop will remain north of
our forecast area but will keep an eye on it.
&&
.SHORT TERM /Saturday through Monday/...
Issued at 217 PM EDT Fri Jun 10 2016
GFS and NAM continue to suggest the strong ridge axis over the
middle mississippi river valley building east across the indiana
on Saturday. Forecast soundings remain dry...showing 700mb temps
near 10c and convective temps near 90. Thus a few-sct CU will be
possible during the afternoon...however deep convection is not
expected. Will again trend highs at or above mavmos given the very
warm air mass in place across Central Indiana with 850mb temps
near 20c.
GFS and NAM then suggest a strong short wave pushing across Quebec
and Eastern Ontario on Saturday night...pushing an associated cold
front across the Great lakes and into Indiana by Sunday morning.
Best forcing and moisture remains well northeast of Indiana.
Forecast soundings and time heights fail to become saturated at
all as subsidence remains in place. Aloft...the GFS depicts
protective...sharp ridging in place over central Indiana through
sunday night and into Monday. On Sunday...again 700mb temps are
expected...thus effectively capping deep convection. Will again
trend lows on Saturday night warmer than mavmos...particularly in
the urban heat islands again due to strong daytime heating. Highs
on sunday should still reach levels above mavmos given the warm
air in place aloft. However northerly winds in the wake of the
cool front on Sunday should result in cooler highs on Sunday
compared to Saturday.
GFS then shows High pressure in the wake of the cool front
settling across Indiana and Ohio on Sunday Night and
Monday...once again providing dry weather. It appears the surface
high should drift far enough southeast that warm...and humid
southwest surface flow will once again establish itself across
central Indiana by Monday afternoon. Thus will trend Sunday Night
lows cooler than expected persistence and HIghs on Monday warmer
than expected persistence.
&&
.LONG TERM /Monday Night through Friday/...
Issued at 258 PM EDT Fri Jun 10 2016
Guidance continues to depict a potentially active long term period
as upper ridging breaks down and a slow moving closed upper low
moves into the region. While at least the early days of the period
do not particularly look like washouts, cannot necessarily pin down
one particular period of dryness, so will have to carry thunderstorm
chances each period throughout the long term.
Temperatures will remain warm but gradually cool back to near normal
during the period, and perhaps even slightly below normal at the
very end of the 7 days as the upper low moves through the area.
Blended initialization handled things relatively well and few
changes were required.
&&
.AVIATION /Discussion for the 110600Z TAFS/...
Issued at 1241 AM EDT Sat Jun 11 2016
Convection currently over the southern Great Lakes not expected to affect
the terminals through at least 111800Z based on position of 850mb thermal
ridge and enhanced flow.
Some limited diurnal cloud based around 040 may develop towards midday
Saturday. Visibilities unrestricted.
Surface winds 190-210 degrees at 5-8 kts overnight expected to become
230-260 degrees at 10-13 kts by midday Saturday.
&&
.IND Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TUCEK
SHORT TERM...PUMA
LONG TERM...NIELD
AVIATION...JAS/CP
Area Forecast Discussion
National Weather Service Indianapolis IN
1223 AM EDT SAT JUN 11 2016
.UPDATE...
The NEAR TERM Section has been updated below.
&&
.SYNOPSIS...
Issued at 217 PM EDT Fri Jun 10 2016
Hot summer weather is expected this weekend as strong high
pressure over the southeastern states pushes warm and moist air
into central Indiana on southwesterly winds.
A cold front will push throughout northeastern United States on
Saturday night...bringing a glancing blow of cooler air to
Central Indiana for Sunday. The front is not expected to result in
precipitation across Central Indiana.
Thunderstorm and precipitation chances will increase next work
week as several upper weather level disturbances are expected to
move our way.
&&
.NEAR TERM /Early This Morning/...
Issued at 1220 AM EDT Sat Jun 11 2016
Have slowed the fall in temperatures and dewpoints through
daybreak as southwest flow has been maintaining dewpoints
and temps slightly higher than expected.
Thus far outflow boundary in northern Illinois from decaying
Wisconsin convection has yet to fire any new development.
Anticipate any precipitation that does develop will remain north
of our forecast area but will keep an eye on it.
&&
.SHORT TERM /Saturday through Monday/...
Issued at 217 PM EDT Fri Jun 10 2016
GFS and NAM continue to suggest the strong ridge axis over the
middle mississippi river valley building east across the indiana
on Saturday. Forecast soundings remain dry...showing 700mb temps
near 10c and convective temps near 90. Thus a few-sct CU will be
possible during the afternoon...however deep convection is not
expected. Will again trend highs at or above mavmos given the very
warm air mass in place across Central Indiana with 850mb temps
near 20c.
GFS and NAM then suggest a strong short wave pushing across Quebec
and Eastern Ontario on Saturday night...pushing an associated cold
front across the Great lakes and into Indiana by Sunday morning.
Best forcing and moisture remains well northeast of Indiana.
Forecast soundings and time heights fail to become saturated at
all as subsidence remains in place. Aloft...the GFS depicts
protective...sharp ridging in place over central Indiana through
sunday night and into Monday. On Sunday...again 700mb temps are
expected...thus effectively capping deep convection. Will again
trend lows on Saturday night warmer than mavmos...particularly in
the urban heat islands again due to strong daytime heating. Highs
on sunday should still reach levels above mavmos given the warm
air in place aloft. However northerly winds in the wake of the
cool front on Sunday should result in cooler highs on Sunday
compared to Saturday.
GFS then shows High pressure in the wake of the cool front
settling across Indiana and Ohio on Sunday Night and
Monday...once again providing dry weather. It appears the surface
high should drift far enough southeast that warm...and humid
southwest surface flow will once again establish itself across
central Indiana by Monday afternoon. Thus will trend Sunday Night
lows cooler than expected persistence and HIghs on Monday warmer
than expected persistence.
&&
.LONG TERM /Monday Night through Friday/...
Issued at 258 PM EDT Fri Jun 10 2016
Guidance continues to depict a potentially active long term period
as upper ridging breaks down and a slow moving closed upper low
moves into the region. While at least the early days of the period
do not particularly look like washouts, cannot necessarily pin down
one particular period of dryness, so will have to carry thunderstorm
chances each period throughout the long term.
Temperatures will remain warm but gradually cool back to near normal
during the period, and perhaps even slightly below normal at the
very end of the 7 days as the upper low moves through the area.
Blended initialization handled things relatively well and few
changes were required.
&&
.AVIATION /Discussion for the 110300Z KIND TAF Update/...
Issued at 1023 PM EDT Fri Jun 10 2016
No significant changes made to the forecast at this time. Previous
discussion follows.
Limited diurnal cloud based around 045 expected to dissipate with
sunset. No other significant cloud expected tonight, along with
unrestricted visibility.
Surface winds 200-230 degrees at 8-12 kts early this evening will
diminish to 5-8 kts after sunset.
&&
.IND Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TUCEK
SHORT TERM...PUMA
LONG TERM...NIELD
AVIATION...JAS
Area Forecast Discussion
National Weather Service Indianapolis IN
1223 AM EDT SAT JUN 11 2016
.UPDATE...
The NEAR TERM Section has been updated below.
&&
.SYNOPSIS...
Issued at 217 PM EDT Fri Jun 10 2016
Hot summer weather is expected this weekend as strong high
pressure over the southeastern states pushes warm and moist air
into central Indiana on southwesterly winds.
A cold front will push throughout northeastern United States on
Saturday night...bringing a glancing blow of cooler air to
Central Indiana for Sunday. The front is not expected to result in
precipitation across Central Indiana.
Thunderstorm and precipitation chances will increase next work
week as several upper weather level disturbances are expected to
move our way.
&&
.NEAR TERM /Early This Morning/...
Issued at 1220 AM EDT Sat Jun 11 2016
Have slowed the fall in temperatures and dewpoints through
daybreak as southwest flow has been maintaining dewpoints
and temps slightly higher than expected.
Thus far outflow boundary in northern Illinois from decaying
Wisconsin convection has yet to fire any new development.
Anticipate any precipitation that does develop will remain north
of our forecast area but will keep an eye on it.
&&
.SHORT TERM /Saturday through Monday/...
Issued at 217 PM EDT Fri Jun 10 2016
GFS and NAM continue to suggest the strong ridge axis over the
middle mississippi river valley building east across the indiana
on Saturday. Forecast soundings remain dry...showing 700mb temps
near 10c and convective temps near 90. Thus a few-sct CU will be
possible during the afternoon...however deep convection is not
expected. Will again trend highs at or above mavmos given the very
warm air mass in place across Central Indiana with 850mb temps
near 20c.
GFS and NAM then suggest a strong short wave pushing across Quebec
and Eastern Ontario on Saturday night...pushing an associated cold
front across the Great lakes and into Indiana by Sunday morning.
Best forcing and moisture remains well northeast of Indiana.
Forecast soundings and time heights fail to become saturated at
all as subsidence remains in place. Aloft...the GFS depicts
protective...sharp ridging in place over central Indiana through
sunday night and into Monday. On Sunday...again 700mb temps are
expected...thus effectively capping deep convection. Will again
trend lows on Saturday night warmer than mavmos...particularly in
the urban heat islands again due to strong daytime heating. Highs
on sunday should still reach levels above mavmos given the warm
air in place aloft. However northerly winds in the wake of the
cool front on Sunday should result in cooler highs on Sunday
compared to Saturday.
GFS then shows High pressure in the wake of the cool front
settling across Indiana and Ohio on Sunday Night and
Monday...once again providing dry weather. It appears the surface
high should drift far enough southeast that warm...and humid
southwest surface flow will once again establish itself across
central Indiana by Monday afternoon. Thus will trend Sunday Night
lows cooler than expected persistence and HIghs on Monday warmer
than expected persistence.
&&
.LONG TERM /Monday Night through Friday/...
Issued at 258 PM EDT Fri Jun 10 2016
Guidance continues to depict a potentially active long term period
as upper ridging breaks down and a slow moving closed upper low
moves into the region. While at least the early days of the period
do not particularly look like washouts, cannot necessarily pin down
one particular period of dryness, so will have to carry thunderstorm
chances each period throughout the long term.
Temperatures will remain warm but gradually cool back to near normal
during the period, and perhaps even slightly below normal at the
very end of the 7 days as the upper low moves through the area.
Blended initialization handled things relatively well and few
changes were required.
&&
.AVIATION /Discussion for the 110300Z KIND TAF Update/...
Issued at 1023 PM EDT Fri Jun 10 2016
No significant changes made to the forecast at this time. Previous
discussion follows.
Limited diurnal cloud based around 045 expected to dissipate with
sunset. No other significant cloud expected tonight, along with
unrestricted visibility.
Surface winds 200-230 degrees at 8-12 kts early this evening will
diminish to 5-8 kts after sunset.
&&
.IND Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...TUCEK
SHORT TERM...PUMA
LONG TERM...NIELD
AVIATION...JAS
Area Forecast Discussion
National Weather Service Indianapolis IN
1023 PM EDT FRI JUN 10 2016
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 217 PM EDT Fri Jun 10 2016
Hot summer weather is expected this weekend as strong high
pressure over the southeastern states pushes warm and moist air
into central Indiana on southwesterly winds.
A cold front will push throughout northeastern United States on
Saturday night...bringing a glancing blow of cooler air to
Central Indiana for Sunday. The front is not expected to result in
precipitation across Central Indiana.
Thunderstorm and precipitation chances will increase next work
week as several upper weather level disturbances are expected to
move our way.
&&
.NEAR TERM /Tonight/...
Issued at 934 PM EDT Fri Jun 10 2016
The HRRR reflectivity progs have the central Wisconsin and
northeastern Iowa convection falling apart overnight as it
approaches central Indiana. Thus, will keep pops out but keep a
close eye on it.
Previous discussion follows...
Issued at 656 PM EDT Fri Jun 10 2016
Pulled the small pops northeast based on quite radar and sunset
coming up in a couple of hours.
Previous discussion follows...
Issued at 217 PM EDT Fri Jun 10 2016
Surface analysis early this morning shows low pressure over the
upper midwest with a warm front extending southeast across
Wisconsin into southern Michigan and NW ohio. High pressure was
found across eastern Kentucky. South to southwest surface flow was
in place across Central Indiana and dew point temps were in the
upper 60s to near 70. Earlier Thunderstorms have weakened and
exited the area...drifting into SW ohio. Water vapor imagery
generally shows a broad ridging in place over the CONUS...with SW
flow aloft over the intermountain west...streaming into the
northern plains...before becoming NW Flow across the Great Lakes
and Northeast. Tropical plumes and gulf moisture were effectively
cut off from reaching Central Indiana.
Dry weather is expected to persist tonight as the models continue
to suggest the warm front will lift northeast...away from central
Indiana and the Surface High to the south will continue to remain
the main player in our weather. This will result in subsidence
along with a dry column as seen within the time height sections
and the forecast soundings. Very warm air mass looks to remain in
place across Central Indiana overnight as 850mb temps continue to
reside near 20c. thus will trend toward a mostly clear sky tonight
and trend lows at or above mavmos...particularly at the urban heat
islands.
&&
.SHORT TERM /Saturday through Monday/...
Issued at 217 PM EDT Fri Jun 10 2016
GFS and NAM continue to suggest the strong ridge axis over the
middle mississippi river valley building east across the indiana
on Saturday. Forecast soundings remain dry...showing 700mb temps
near 10c and convective temps near 90. Thus a few-sct CU will be
possible during the afternoon...however deep convection is not
expected. Will again trend highs at or above mavmos given the very
warm air mass in place across Central Indiana with 850mb temps
near 20c.
GFS and NAM then suggest a strong short wave pushing across Quebec
and Eastern Ontario on Saturday night...pushing an associated cold
front across the Great lakes and into Indiana by Sunday morning.
Best forcing and moisture remains well northeast of Indiana.
Forecast soundings and time heights fail to become saturated at
all as subsidence remains in place. Aloft...the GFS depicts
protective...sharp ridging in place over central Indiana through
sunday night and into Monday. On Sunday...again 700mb temps are
expected...thus effectively capping deep convection. Will again
trend lows on Saturday night warmer than mavmos...particularly in
the urban heat islands again due to strong daytime heating. Highs
on sunday should still reach levels above mavmos given the warm
air in place aloft. However northerly winds in the wake of the
cool front on Sunday should result in cooler highs on Sunday
compared to Saturday.
GFS then shows High pressure in the wake of the cool front
settling across Indiana and Ohio on Sunday Night and
Monday...once again providing dry weather. It appears the surface
high should drift far enough southeast that warm...and humid
southwest surface flow will once again establish itself across
central Indiana by Monday afternoon. Thus will trend Sunday Night
lows cooler than expected persistence and HIghs on Monday warmer
than expected persistence.
&&
.LONG TERM /Monday Night through Friday/...
Issued at 258 PM EDT Fri Jun 10 2016
Guidance continues to depict a potentially active long term period
as upper ridging breaks down and a slow moving closed upper low
moves into the region. While at least the early days of the period
do not particularly look like washouts, cannot necessarily pin down
one particular period of dryness, so will have to carry thunderstorm
chances each period throughout the long term.
Temperatures will remain warm but gradually cool back to near normal
during the period, and perhaps even slightly below normal at the
very end of the 7 days as the upper low moves through the area.
Blended initialization handled things relatively well and few
changes were required.
&&
.AVIATION /Discussion for the 110300Z KIND TAF Update/...
Issued at 1023 PM EDT Fri Jun 10 2016
No significant changes made to the forecast at this time. Previous
discussion follows.
Limited diurnal cloud based around 045 expected to dissipate with
sunset. No other significant cloud expected tonight, along with
unrestricted visibility.
Surface winds 200-230 degrees at 8-12 kts early this evening will
diminish to 5-8 kts after sunset.
&&
.IND Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA/MK
SHORT TERM...PUMA
LONG TERM...NIELD
AVIATION...JAS
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
251 AM CDT SAT JUN 11 2016
.SHORT TERM...(Today and Tonight)
Issued at 251 AM CDT SAT JUN 11 2016
Cluster of convection continues across eastern Iowa and to the
southwest in the panhandles area of the high plains, while the
forecast area remains warm and dry. While outflow from Iowa storms
is moving to the southwest, unlikely that more than clouds will make
it this far southwest. Upper ridge continues to move eastward over
the area with weak upper low over Oklahoma and north Texas moving
very little through Sunday. End result will be high temperatures
just a degree or two warmer than Friday, and another night with lows
in the 70s. Afternoon heat indicies still hover in the upper 90s
near 100 and will be the primary concern for the short term.
.LONG TERM...(Sunday through Friday)
Issued at 251 AM CDT SAT JUN 11 2016
On Sunday the models are showing the remnant mid level energy
located over southern KS. This means weak forcing may be present
within an uncapped environment. Therefore there is a small chance
for a few showers and storms during the afternoon. A cold front will
stretch from western KS into north central NE. Storms are expected
to develop along this front during the afternoon as well. This
activity will try and move southeastward towards the forecast area
Sunday night. The more robust convection appears to remain across
western KS closer to the low level jet. By early Monday morning the
cape will have decrease, but possibly still around 1000 j/kg.
Although the shear will be fairly weak so do not expect much
organization. On Monday the mid level trough still remains over the
Rockies, which will keep the fronts from moving much overnight. A
majority of the models depict precip in the area during the day,
which could be due to lingering outflow boundaries. The shortwave
trough will lift out over the plains on Tuesday, but there are still
timing differences among the models. A surface low pressure will
move across northern KS during this time frame, and a front will
approach from the west. Ahead of the front instability will be very
high, and deep layer shear increases due to the wave. Therefore
strong to severe storms will be possible on Tuesday, but the details
are still uncertain. As that system moves over the Midwest
conditions will dry out again. Towards next weekend that mid level
system cuts off somewhere near the mid MS valley, and possibly
begins to retrograde westward. This will at least provide the
area with slightly cooler temperatures during this period.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1125 PM CDT FRI JUN 10 2016
VFR continues at terminals with southerly winds increasing abv 10
kts aft 15Z. Confidence remains low and marginal for LLWS based
on latest guidance through sunrise. Current indication is a
gradual increase in speed up to 35 kts at 1000 ft.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...67
LONG TERM...Sanders
AVIATION...Prieto
Area Forecast Discussion
National Weather Service Goodland KS
1120 PM MDT FRI JUN 10 2016
.SHORT TERM...(This afternoon through Saturday)
Issued at 120 PM MDT Fri Jun 10 2016
Early afternoon WV imagery and RAP analysis indicates ridging
extending across Colorado with axis centered across our CWA. A
shortwave trough is east of our CWA. At the surface low pressure
is in place across eastern Colorado, with a secondary surface
trough axis near McCook Nebraska extending southeast through our
CWA.
This afternoon-Tonight: Weak forcing and moisture is rotating into
the rockies and has led to thunderstorm development across higher
terrain in south central Colorado. Some hi res guidance indicates
possible development and movement towards our western CWA, however
if this happens it will coincide with loss of daytime
heating/instability and confidence is low this would make it into
our CWA (particularly considering the mean storm motion and weak
flow aloft away from our CWA). Otherwise subsidence and a deep dry
air mass will preclude local thunderstorm development this
afternoon/evening. Relatively light winds and clear skies should
support another night of good radiational cooling, so expect
similar lows as last night (around 60F west to around 70F east).
Saturday: Upper level ridge shifts east while trough deepens in
this west. This may allow for a little more forcing to shift
eastward into our CWA, and there will be good instability in
place. Models are still indicating a very dry air mass in place,
and most guidance keeps dry conditions in place locally. Only
NMM/ARW supporting isolated thunderstorm activity Saturday
afternoon. I kept forecast dry for now, though I couldn`t rule of
a stray elevated thunderstorm. As the surface trough shifts east
and heights begin to fall, the air mass slowly "cools" over our
CWA. Temps aloft projected by guidance are very similar to was was
realized Thursday, and similar temperatures (low-mid 90s) would be
anticipated. This is a little lower than today, but still above
normal by 10-15 degrees.
.LONG TERM...(Saturday night through Friday)
Issued at 209 PM MDT Fri Jun 10 2016
The lee surface trough that strengthens along the Front Range on
Saturday begins moving east into the forecast area Saturday night
ahead of a cold front expected to push through the forecast area
on Sunday evening. This is accompanied by the short wave a aloft
that rides up the back side of the ridge late Saturday and then
tops the ridge late Sunday as it moves through Nebraska.
While models inconsistently hint at a few showers across the
central high plains region Saturday night, most likely as a few
storms form over the higher terrain of the Raton ridge and Palmer
divide, the highest probability of thunderstorms across the area
will occur late Sunday through early Monday morning as the short
wave trough moving through Nebraska turns around the apex of the
decreasing amplitude upper ridge and moves into eastern Kansas by
Monday. Model QPF is showing some possible heavy rains over south
central Nebraska and north central Kansas Sunday night. With
southerly flow extending from the Gulf of Mexico into the central
plains with dewpoints in the middle 60s over the eastern sections
of the forecast area, don`t feel this is out of line.
On Monday night through Tuesday night, the upper trough that has
been approaching through the southwestern U.S. will lift out
across the Rockies and Central High Plains region for another
round of storms mainly from late Monday through early Tuesday with
activity diminishing by Tuesday night.
As the trough deepens into a closed low over the northern plains
and moves out of the region and the upper ridge redevelops over
the High Plains, dry and hot temperatures return to the region
during the latter portion of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1120 PM MDT Fri Jun 10 2016
VFR conditions forecast over the next 24 hours. High pressure
ridge will prevent development of any showers and thunderstorms.
Moisture advection from the south lead to formation of daytime
cumulus around 5000-7000 feet after 18z. South winds will continue
through the TAF period. Am monitoring an outflow boundary over southwest
Nebraska to see if it reaches KMCK in the near-term. This would
shift winds to the northeast for a few hours. Still anticipate south
winds to strengthen tomorrow as a lee trough deepens east of the
Rocky Mountains.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...RRH
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1133 PM CDT FRI JUN 10 2016
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Saturday)
Issued at 311 PM CDT FRI JUN 10 2016
Upper level ridge continues across the Central Plains this
afternoon. Weak upper trough was filling across central and
northeast Kansas this morning. Surface trough continues across the
western high plains with axis of mid to upper 60s dewpoints across
central and eastern Kansas. Afternoon cumulus has developed across
the area and should be on the decrease toward sunset with the loss
of heating. With little change in airmass since yesterday expect
low temperatures from the upper 60s to mid 70s overnight. On
Saturday, 850 mb temperatures warm a degree or two from today.
Forecast soundings suggest mixing down from around 850 mb with
highs mainly in the low to mid 90s. Afternoon dew points in the
upper 60s to around 70 will yield heat indices in the upper 90s to
around 100 degrees in the afternoon. With no forcing aloft or at
the surface and soundings showing weak cap remaining in place
Saturday afternoon, will keep the forecast dry.
.LONG TERM...(Saturday Night through Friday)
Issued at 311 PM CDT FRI JUN 10 2016
Last part of the weekend should remain dry and very warm with high
temps still in the 90s and heat indices into the mid to upper 90s.
Precip chances increase into Monday as and overnight complex of
storms appears to form over west central Nebraska and slowly make
its way near or into East Central Kansas by early morning. It will
be pushed along by a weak boundary and without significant forcing
aloft, the trend based on 12Z model data will be to decrease in
intensity and whatever rain and thunderstorms are left. Storms may
linger into the morning and early afternoon over the forecast area,
so have maintained chance POPs over most of the area. It isn`t until
the Tuesday time frame and overnight Wednesday that a tight compact
upper low forms and undergoes cyclogenesis as split southern stream
flow aloft ejects out of the Rockies into the Central Plains. Best
indication at this time is that the forcing aloft will increase over
western and northern portions of the forecast area giving the best
chance to strong to perhaps severe storms. With indications that
there will be a remnant EML in place, there could be more isolated
activity. But with the upper low deepening quickly, steep lapse
rates aloft with favorable shear, due to the upper low, could result
in mostly a severe hail and wind threat. Again, still not highly
confident in the overall set up or other forcing mechanisms such as
a possible modified dryline mixing into the area. Also, guidance
does vary too much at this time to be on the high end chance POPs.
Rest of the week after this does look dry once again with perhaps
slight chance POPs as the upper low essentially becomes cut off from
the upper flow aloft and eventually fills over the Ohio River
Valley. Meanwhile temps cool back to the mid to upper 80s by the
end of the week as northeast flow sets up with surface high
pressure in place.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1125 PM CDT FRI JUN 10 2016
VFR continues at terminals with southerly winds increasing abv 10
kts aft 15Z. Confidence remains low and marginal for LLWS based
on latest guidance through sunrise. Current indication is a
gradual increase in speed up to 35 kts at 1000 ft.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Drake
AVIATION...Prieto
Area Forecast Discussion
National Weather Service Wichita KS
1126 PM CDT FRI JUN 10 2016
.SYNOPSIS...
Issued at 326 PM CDT Fri Jun 10 2016
A ridge that has been dominating the majority of the
CONUS has begun its eastward progression at 700 and 850mb towards
the East Coast. There is a trough behind this ridge that is centered
over the central Canadian provinces. This is obviously well off to
the north and will have ridging behind it with another trough hot on
its tail; the expectation is for this wave to get its act together
through the weekend.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 326 PM CDT Fri Jun 10 2016
A persistent ridging over the area continues the
stagnant conditions of 90 degree temperatures which is 5 to 10
degrees above seasonal normal. There is a slight chance of
convection due to diurnal heating late this afternoon to evening
over portions of south central Kansas; any storms would be
isolated and will quickly dissipate after the sun goes down.
The influence of the next trough begins to make its influence for
the latter part of the weekend into the first part of the week.
Chances of showers and thunderstorms will be highest over central
Kansas on Sunday evening to northeast Kansas for Monday. Some of the
storms could get a little rowdy on Monday with 0-3km MUCAPE values
ranging from 1500 to 4000 J/kg depending on which model is
considered as the GFS indicates values on the higher end. Bulk shear
vectors from 0-6km are 10 to 30 knots which could further aid
development. Further model runs with the advancing period will help
to better determine the potential and scale of such activity.
Minimal changes were made to the ongoing forecast given model
consistency and a benign pattern for the very near term.
.LONG TERM...(Tuesday through Friday)
Issued at 326 PM CDT Fri Jun 10 2016
The low deepens for the middle of the week to stay over
the central United States from Tuesday through Thursday. Bulk of the
precipitation appears to stay around the center of the closed low
which will be over the Northern Plains. In this part of the forecast
period, there is only lingering showers and potential thunderstorms
for Tuesday as the low pushes northeast. Despite this low pressure
system, there is little associated cold air advection behind it
which means high temperatures in the 90s will persist through the
extended. After a period of fairly consistent model agreement, there
is complete divergence at the very last part of the forecast and
into next weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1126 PM CDT Fri Jun 10 2016
VFR conditions expected to prevail thru the forecast valid
period. Diurnally gusty south winds may not be quite as strong
as the past couple days on Saturday. A few cumulus can be
expected during the afternoon though deep convection/storms
are not anticipated across the area.
KED
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 72 93 72 92 / 10 10 10 10
Hutchinson 72 93 72 93 / 20 10 10 10
Newton 71 92 71 92 / 10 10 0 10
ElDorado 71 91 72 91 / 10 10 0 10
Winfield-KWLD 71 91 72 90 / 10 10 0 20
Russell 70 95 70 94 / 10 10 10 10
Great Bend 70 95 70 94 / 20 10 10 10
Salina 72 94 72 95 / 10 10 10 10
McPherson 72 93 72 93 / 20 10 10 10
Coffeyville 70 90 71 90 / 10 0 0 20
Chanute 70 90 71 90 / 10 0 0 10
Iola 70 90 71 90 / 10 0 0 10
Parsons-KPPF 70 90 71 90 / 10 0 0 10
&&
.ICT Watches/Warnings/Advisories...None.
&&
$$
SYNOPSIS...VJP
SHORT TERM...VJP
LONG TERM...VJP
AVIATION...KED
Area Forecast Discussion
National Weather Service Wichita KS
632 PM CDT FRI JUN 10 2016
.SYNOPSIS...
Issued at 326 PM CDT Fri Jun 10 2016
A ridge that has been dominating the majority of the
CONUS has begun its eastward progression at 700 and 850mb towards
the East Coast. There is a trough behind this ridge that is centered
over the central Canadian provinces. This is obviously well off to
the north and will have ridging behind it with another trough hot on
its tail; the expectation is for this wave to get its act together
through the weekend.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 326 PM CDT Fri Jun 10 2016
A persistent ridging over the area continues the
stagnant conditions of 90 degree temperatures which is 5 to 10
degrees above seasonal normal. There is a slight chance of
convection due to diurnal heating late this afternoon to evening
over portions of south central Kansas; any storms would be
isolated and will quickly dissipate after the sun goes down.
The influence of the next trough begins to make its influence for
the latter part of the weekend into the first part of the week.
Chances of showers and thunderstorms will be highest over central
Kansas on Sunday evening to northeast Kansas for Monday. Some of the
storms could get a little rowdy on Monday with 0-3km MUCAPE values
ranging from 1500 to 4000 J/kg depending on which model is
considered as the GFS indicates values on the higher end. Bulk shear
vectors from 0-6km are 10 to 30 knots which could further aid
development. Further model runs with the advancing period will help
to better determine the potential and scale of such activity.
Minimal changes were made to the ongoing forecast given model
consistency and a benign pattern for the very near term.
.LONG TERM...(Tuesday through Friday)
Issued at 326 PM CDT Fri Jun 10 2016
The low deepens for the middle of the week to stay over
the central United States from Tuesday through Thursday. Bulk of the
precipitation appears to stay around the center of the closed low
which will be over the Northern Plains. In this part of the forecast
period, there is only lingering showers and potential thunderstorms
for Tuesday as the low pushes northeast. Despite this low pressure
system, there is little associated cold air advection behind it
which means high temperatures in the 90s will persist through the
extended. After a period of fairly consistent model agreement, there
is complete divergence at the very last part of the forecast and
into next weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 633 PM CDT Fri Jun 10 2016
VFR conditions expected to prevail thru the forecast valid
period. Diurnally driven isolated showers/storms are not
expected to affect the terminals this evening. South winds
will also abate late this evening and overnight before
becoming gusty again west of the Kansas turnpike on Saturday
from late morning through the afternoon.
KED
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 72 93 72 92 / 10 10 10 10
Hutchinson 72 93 72 93 / 20 10 10 10
Newton 71 92 71 92 / 10 10 0 10
ElDorado 71 91 72 91 / 10 10 0 10
Winfield-KWLD 71 91 72 90 / 10 10 0 20
Russell 70 95 70 94 / 10 10 10 10
Great Bend 70 95 70 94 / 20 10 10 10
Salina 72 94 72 95 / 10 10 10 10
McPherson 72 93 72 93 / 20 10 10 10
Coffeyville 70 90 71 90 / 10 0 0 20
Chanute 70 90 71 90 / 10 0 0 10
Iola 70 90 71 90 / 10 0 0 10
Parsons-KPPF 70 90 71 90 / 10 0 0 10
&&
.ICT Watches/Warnings/Advisories...None.
&&
$$
SYNOPSIS...VJP
SHORT TERM...VJP
LONG TERM...VJP
AVIATION...KED
Area Forecast Discussion
National Weather Service Wichita KS
632 PM CDT FRI JUN 10 2016
.SYNOPSIS...
Issued at 326 PM CDT Fri Jun 10 2016
A ridge that has been dominating the majority of the
CONUS has begun its eastward progression at 700 and 850mb towards
the East Coast. There is a trough behind this ridge that is centered
over the central Canadian provinces. This is obviously well off to
the north and will have ridging behind it with another trough hot on
its tail; the expectation is for this wave to get its act together
through the weekend.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 326 PM CDT Fri Jun 10 2016
A persistent ridging over the area continues the
stagnant conditions of 90 degree temperatures which is 5 to 10
degrees above seasonal normal. There is a slight chance of
convection due to diurnal heating late this afternoon to evening
over portions of south central Kansas; any storms would be
isolated and will quickly dissipate after the sun goes down.
The influence of the next trough begins to make its influence for
the latter part of the weekend into the first part of the week.
Chances of showers and thunderstorms will be highest over central
Kansas on Sunday evening to northeast Kansas for Monday. Some of the
storms could get a little rowdy on Monday with 0-3km MUCAPE values
ranging from 1500 to 4000 J/kg depending on which model is
considered as the GFS indicates values on the higher end. Bulk shear
vectors from 0-6km are 10 to 30 knots which could further aid
development. Further model runs with the advancing period will help
to better determine the potential and scale of such activity.
Minimal changes were made to the ongoing forecast given model
consistency and a benign pattern for the very near term.
.LONG TERM...(Tuesday through Friday)
Issued at 326 PM CDT Fri Jun 10 2016
The low deepens for the middle of the week to stay over
the central United States from Tuesday through Thursday. Bulk of the
precipitation appears to stay around the center of the closed low
which will be over the Northern Plains. In this part of the forecast
period, there is only lingering showers and potential thunderstorms
for Tuesday as the low pushes northeast. Despite this low pressure
system, there is little associated cold air advection behind it
which means high temperatures in the 90s will persist through the
extended. After a period of fairly consistent model agreement, there
is complete divergence at the very last part of the forecast and
into next weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 633 PM CDT Fri Jun 10 2016
VFR conditions expected to prevail thru the forecast valid
period. Diurnally driven isolated showers/storms are not
expected to affect the terminals this evening. South winds
will also abate late this evening and overnight before
becoming gusty again west of the Kansas turnpike on Saturday
from late morning through the afternoon.
KED
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 72 93 72 92 / 10 10 10 10
Hutchinson 72 93 72 93 / 20 10 10 10
Newton 71 92 71 92 / 10 10 0 10
ElDorado 71 91 72 91 / 10 10 0 10
Winfield-KWLD 71 91 72 90 / 10 10 0 20
Russell 70 95 70 94 / 10 10 10 10
Great Bend 70 95 70 94 / 20 10 10 10
Salina 72 94 72 95 / 10 10 10 10
McPherson 72 93 72 93 / 20 10 10 10
Coffeyville 70 90 71 90 / 10 0 0 20
Chanute 70 90 71 90 / 10 0 0 10
Iola 70 90 71 90 / 10 0 0 10
Parsons-KPPF 70 90 71 90 / 10 0 0 10
&&
.ICT Watches/Warnings/Advisories...None.
&&
$$
SYNOPSIS...VJP
SHORT TERM...VJP
LONG TERM...VJP
AVIATION...KED
Area Forecast Discussion
National Weather Service Goodland KS
516 PM MDT FRI JUN 10 2016
.SHORT TERM...(This afternoon through Saturday)
Issued at 120 PM MDT Fri Jun 10 2016
Early afternoon WV imagery and RAP analysis indicates ridging
extending across Colorado with axis centered across our CWA. A
shortwave trough is east of our CWA. At the surface low pressure
is in place across eastern Colorado, with a secondary surface
trough axis near McCook Nebraska extending southeast through our
CWA.
This afternoon-Tonight: Weak forcing and moisture is rotating into
the rockies and has led to thunderstorm development across higher
terrain in south central Colorado. Some hi res guidance indicates
possible development and movement towards our western CWA, however
if this happens it will coincide with loss of daytime
heating/instability and confidence is low this would make it into
our CWA (particularly considering the mean storm motion and weak
flow aloft away from our CWA). Otherwise subsidence and a deep dry
air mass will preclude local thunderstorm development this
afternoon/evening. Relatively light winds and clear skies should
support another night of good radiational cooling, so expect
similar lows as last night (around 60F west to around 70F east).
Saturday: Upper level ridge shifts east while trough deepens in
this west. This may allow for a little more forcing to shift
eastward into our CWA, and there will be good instability in
place. Models are still indicating a very dry air mass in place,
and most guidance keeps dry conditions in place locally. Only
NMM/ARW supporting isolated thunderstorm activity Saturday
afternoon. I kept forecast dry for now, though I couldn`t rule of
a stray elevated thunderstorm. As the surface trough shifts east
and heights begin to fall, the air mass slowly "cools" over our
CWA. Temps aloft projected by guidance are very similar to was was
realized Thursday, and similar temperatures (low-mid 90s) would be
anticipated. This is a little lower than today, but still above
normal by 10-15 degrees.
.LONG TERM...(Saturday night through Friday)
Issued at 209 PM MDT Fri Jun 10 2016
The lee surface trough that strengthens along the Front Range on
Saturday begins moving east into the forecast area Saturday night
ahead of a cold front expected to push through the forecast area
on Sunday evening. This is accompanied by the short wave a aloft
that rides up the back side of the ridge late Saturday and then
tops the ridge late Sunday as it moves through Nebraska.
While models inconsistently hint at a few showers across the
central high plains region Saturday night, most likely as a few
storms form over the higher terrain of the Raton ridge and Palmer
divide, the highest probability of thunderstorms across the area
will occur late Sunday through early Monday morning as the short
wave trough moving through Nebraska turns around the apex of the
decreasing amplitude upper ridge and moves into eastern Kansas by
Monday. Model QPF is showing some possible heavy rains over south
central Nebraska and north central Kansas Sunday night. With
southerly flow extending from the Gulf of Mexico into the central
plains with dewpoints in the middle 60s over the eastern sections
of the forecast area, don`t feel this is out of line.
On Monday night through Tuesday night, the upper trough that has
been approaching through the southwestern U.S. will lift out
across the Rockies and Central High Plains region for another
round of storms mainly from late Monday through early Tuesday with
activity diminishing by Tuesday night.
As the trough deepens into a closed low over the northern plains
and moves out of the region and the upper ridge redevelops over
the High Plains, dry and hot temperatures return to the region
during the latter portion of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 516 PM MDT Fri Jun 10 2016
VFR conditions are forecast over the next 24 hours at both sites.
Due to a ridge of high pressure developing over the High Plains,
am also not anticipating any precipitation. South winds will
persist over the next 24 hours. As a lee trough strengthens
tomorrow, expect south winds to intensify by tomorrow afternoon.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...RRH
Area Forecast Discussion
National Weather Service Phoenix AZ
855 AM MST SAT JUN 11 2016
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
Mid-level drying noted on morning water vapor satellite loops but
still ample and above normal low level moisture surface sampled
across the area. Morning dewpoints sitting solidly in the upper 50s
to low 60s for many lower desert sites - values typically seen
several weeks from now and not in early June. Neighboring RAOBs and
the few AM AMDAR soundings out of KPHX with a dewpoint trace
indicate drying above 700mb and once daytime heating and mixing gets
underway, the elevated dewpoint readings should begin to thin and
lower by the afternoon. Cloud cover straddles the AZ/NM state line
from the Intl Border to the Four Corners and some scattered CU were
beginning to develop over Mohave County, near the exiting inverted
wave that brought unsettled conditions to the area yesterday. CU
coverage will certainly be possible today from the Lower CO River
Valley eastward, but any shower/thunder activity will develop first
over the Rim Country and White Mountains. Steering flow is out of
the west and south through the available moisture layers, so anything
that does develop should stay clear of the lower deserts. Only
morning updates incorporated to the grid update were some adjustments
on sky coverage to match current trends as well as hourly dewpoint
and ambient temperatures.
&&
.PREVIOUS DISCUSSION /Issued at 230 AM MST/PDT/...
As the larger synoptic scale ridge axis shifts into the southern
plains early this morning, several shortwaves/vorticity centers are
evident in satellite imagery streaming north on the western periphery
of this high pressure. The primary vorticity center/easterly wave has
already lifted near Las Vegas, however several convectively induced
MCV`s are still evident over NE AZ and SE AZ within the debris cloud
field. Meanwhile, a fuller latitude trough in the westerly flow
across the East Pacific was edging towards the US West Coast, and
effectively enveloping the local forecast area under dryslot
subsidence. This latter East Pacific trough will slowly move across
the SW Conus through early next week and be the primary influence on
weather and temperatures.
Through today, flow aloft will become more predominantly southwest
gradually scouring away moisture through horizontal advection and
vertical mixing. 00Z KTWC sounding data still sampled a daily record
1.49" PWAT, however 00Z KNKX data interrogated substantial drying in
the H8-H5 layer which will undoubtedly overspread the downstream
area (i.e. SE CA and AZ) through today. NAM Bufr forecast soundings
are still reluctant to fully relinquish the 10 g/kg boundary layer
moisture profiles in lower elevation locations this afternoon
resulting in a period of modest instability in a weakly capped
environment. Given trends in satellite and past events under similar
flow patterns, believe upslope regions over the Mogollon Rim and
White Mountains would be more favored for deep convection; and a
vast majority of high resolution models and ensemble systems support
this rational.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast
California/Southwest Arizona including KIPL and KBLH:
Over Phoenix terminals, winds will follow normal diurnal directional
trends with speeds around 5 to 15 kts. Clouds building over the
mountains north and east of Phoenix will be pushed further away from
TAF sites, leaving no aviation concerns through the period. At
Southeast California terminals, winds will be near 5 to 15 kts with
periods of higher gusts possible this afternoon, but overall impacts
to aviation will be minimal.
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday...
Dry air will dominate through the forecast period as high pressure
builds back over the region. As a result, minimum humidities will
drop from 8%-15% on Monday to 5%-10% on Friday. Temperatures will
also be on the rise, with near normal temperatures Monday through
Tuesday, becoming warmer than average on Wednesday with continued
warming through the remainder of the week. Winds will generally
follow normal diurnal directional trends and range from 5-15 mph with
a few periods of afternoon gusts in the typical areas.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...Nolte
PREVIOUS DISCUSSION...MO
AVIATION...Hernandez
FIRE WEATHER...Hernandez/Percha
Area Forecast Discussion
National Weather Service Phoenix AZ
502 AM MST SAT JUN 11 2016
.UPDATE...Updated Aviation and Fire Weather Discussion
&&
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
As the larger synoptic scale ridge axis shifts into the southern
plains early this morning, several shortwaves/vorticity centers are
evident in satellite imagery streaming north on the western
periphery of this high pressure. The primary vorticity
center/easterly wave has already lifted near Las Vegas, however
several convectively induced MCV`s are still evident over NE AZ and
SE AZ within the debris cloud field. Meanwhile, a fuller latitude
trough in the westerly flow across the East Pacific was edging
towards the US West Coast, and effectively enveloping the local
forecast area under dryslot subsidence. This latter East Pacific
trough will slowly move across the SW Conus through early next week
and be the primary influence on weather and temperatures.
Through today, flow aloft will become more predominantly southwest
gradually scouring away moisture through horizontal advection and
vertical mixing. 00Z KTWC sounding data still sampled a daily record
1.49" PWAT, however 00Z KNKX data interrogated substantial drying in
the H8-H5 layer which will undoubtedly overspread the downstream
area (i.e. SE CA and AZ) through today. NAM Bufr forecast soundings
are still reluctant to fully relinquish the 10 g/kg boundary layer
moisture profiles in lower elevation locations this afternoon
resulting in a period of modest instability in a weakly capped
environment. Given trends in satellite and past events under similar
flow patterns, believe upslope regions over the Mogollon Rim and
White Mountains would be more favored for deep convection; and a
vast majority of high resolution models and ensemble systems support
this rational.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast
California/Southwest Arizona including KIPL and KBLH:
Over Phoenix terminals, winds will follow normal diurnal directional
trends with speeds around 5 to 15 kts. Clouds building over the
mountains north and east of Phoenix will be pushed further away from
TAF sites, leaving no aviation concerns through the period. At
Southeast California terminals, winds will be near 5 to 15 kts with
periods of higher gusts possible this afternoon, but overall impacts
to aviation will be minimal.
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday...
Dry air will dominate through the forecast period as high pressure
builds back over the region. As a result, minimum humidities will
drop from 8%-15% on Monday to 5%-10% on Friday. Temperatures will
also be on the rise, with near normal temperatures Monday through
Tuesday, becoming warmer than average on Wednesday with continued
warming through the remainder of the week. Winds will generally
follow normal diurnal directional trends and range from 5-15 mph with
a few periods of afternoon gusts in the typical areas.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...MO
AVIATION...Hernandez
FIRE WEATHER...Hernandez/Percha
Area Forecast Discussion
National Weather Service Phoenix AZ
502 AM MST SAT JUN 11 2016
.UPDATE...Updated Aviation and Fire Weather Discussion
&&
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
As the larger synoptic scale ridge axis shifts into the southern
plains early this morning, several shortwaves/vorticity centers are
evident in satellite imagery streaming north on the western
periphery of this high pressure. The primary vorticity
center/easterly wave has already lifted near Las Vegas, however
several convectively induced MCV`s are still evident over NE AZ and
SE AZ within the debris cloud field. Meanwhile, a fuller latitude
trough in the westerly flow across the East Pacific was edging
towards the US West Coast, and effectively enveloping the local
forecast area under dryslot subsidence. This latter East Pacific
trough will slowly move across the SW Conus through early next week
and be the primary influence on weather and temperatures.
Through today, flow aloft will become more predominantly southwest
gradually scouring away moisture through horizontal advection and
vertical mixing. 00Z KTWC sounding data still sampled a daily record
1.49" PWAT, however 00Z KNKX data interrogated substantial drying in
the H8-H5 layer which will undoubtedly overspread the downstream
area (i.e. SE CA and AZ) through today. NAM Bufr forecast soundings
are still reluctant to fully relinquish the 10 g/kg boundary layer
moisture profiles in lower elevation locations this afternoon
resulting in a period of modest instability in a weakly capped
environment. Given trends in satellite and past events under similar
flow patterns, believe upslope regions over the Mogollon Rim and
White Mountains would be more favored for deep convection; and a
vast majority of high resolution models and ensemble systems support
this rational.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast
California/Southwest Arizona including KIPL and KBLH:
Over Phoenix terminals, winds will follow normal diurnal directional
trends with speeds around 5 to 15 kts. Clouds building over the
mountains north and east of Phoenix will be pushed further away from
TAF sites, leaving no aviation concerns through the period. At
Southeast California terminals, winds will be near 5 to 15 kts with
periods of higher gusts possible this afternoon, but overall impacts
to aviation will be minimal.
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday...
Dry air will dominate through the forecast period as high pressure
builds back over the region. As a result, minimum humidities will
drop from 8%-15% on Monday to 5%-10% on Friday. Temperatures will
also be on the rise, with near normal temperatures Monday through
Tuesday, becoming warmer than average on Wednesday with continued
warming through the remainder of the week. Winds will generally
follow normal diurnal directional trends and range from 5-15 mph with
a few periods of afternoon gusts in the typical areas.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...MO
AVIATION...Hernandez
FIRE WEATHER...Hernandez/Percha
[top]
Area Forecast Discussion
National Weather Service Flagstaff AZ
346 AM MST SAT JUN 11 2016
.SYNOPSIS...Drier southwest flow returns later today and
especially Sunday, with breezy conditions and decreasing shower
activity. A chance of showers and thunderstorms continues on
Monday with a passing trough, before a strong warming and drying
trend for the remainder of next week.
&&
.DISCUSSION...
Low pressure off the southern California coast will approach
Arizona over the coming days, eventually crossing the state on
Monday. In the meantime, chances for showers will continue again
today, though expected to be less widespread than we experienced
on Friday. Even less activity is likely for Sunday, though gustier
southwest winds are anticipated. Monday appears to be our last
chance for showers in the 7-day forecast as the trough passes
across the region. In the wake of the passing trough, drier air
and much warmer daytime temperatures will return under
strengthening high pressure.
&&
.AVIATION...For the 12Z Package...A low pressure system centered
over California will combine with moisture from the south for
isolated showers and thunderstorms today into the early evening
across northern Arizona. Wind gust to 35 kts possible with storms.
Otherwise, look for VFR conditions over next 24 hours. Aviation
discussion not updated for TAF amendments.
&&
.FIRE WEATHER...A low pressure system centered over California
will combine with moisture from the south for isolated showers
and thunderstorms today into the early evening across northern
Arizona. Rainfall amounts look to be on the order of a tenth of an
inch or less. On Sunday, the low will remain over California but
drier air will move over the area with shower and storm activity
shutting down.
Monday through Wednesday...The low center exits from California and
moves across Arizona on Monday inducing a slight chance of showers
and thunderstorms. Behind the low a drier and warmer air mass
will move across Arizona on Tuesday and Wednesday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...KD
AVIATION...McCollum
FIRE WEATHER...McCollum
For Northern Arizona weather information visit
weather.gov/flagstaff
[top]
Area Forecast Discussion
National Weather Service Tucson AZ
234 AM MST SAT JUN 11 2016
.SYNOPSIS...Drier air starts to work in from the west today
pushing the best chance of storms to areas east of Tucson. A few
thunderstorms may occur near the New Mexico border on Sunday. Dry
conditions will prevail next week with a drier air mass over the
area. Daytime temperatures will remain near normal or a few degrees
below normal through Tuesday, then hotter temperatures return next
Wednesday and Thursday.
&&
.DISCUSSION...Radar was quiet across SE Arizona as of 2 am. However
S of Douglas there were isolated showers associated with a decaying
complex. Wouldn`t be surprised if a weak MCV comes out of this
complex and pushes north along the AZ/NM border later this morning.
Precipitable water values remain well above mid-June normals this
morning with values mostly in the 1.00"-1.50" range. Water vapor
imagery showed an upper level low approaching southern CA. Drier air
will start to push in from the west as the day progresses, but
enough will be around across the eastern 2/3rds of the area for
isolated valley/scattered mountains showers and thunderstorms.
Precipitable water values are forecast to be below 1" on Sunday with
a slight chance of storms relegated to the White mountains. High
temperatures this weekend will remain several degrees below normal.
Upper level trof will push across the state on Monday providing
slightly cooler daytime temperatures and further drying of the
atmosphere.
Upper ridge strengthens over the area Tuesday through Friday
resulting in warmer daytime high temperatures.
Outside of this forecast package are likely HOTTER daytime
temperatures as the upper ridge continues to strengthen over the
area. Highs next weekend could rival what occurred earlier this
month. Stay tuned.
&&
.AVIATION...VALID THRU 12/12Z.
KTUS E, few-sct 10-15kft bkn-ovc 20-25kft MSL, isold-wdly sct
-SHRA/-TSRA. W KTUS, skc-sct 12-15kft MSL.
Surface wind mainly less than 10 kts except near thunderstorms.
Aviation discussion not updated for TAF ammendments.
&&
.FIRE WEATHER...Isolated to scattered showers and thunderstorms
again today. A few thunderstorms Sunday will likely be limited to
the higher terrain east of Tucson. Thunderstorm outflows will
occasionally produce brief strong, gusty and erratic winds. Dry
conditions will then prevail area-wide Monday through Friday of next
week. Daytime temperatures will be a few degrees below normal into
early next week, then hotter temperatures return Wednesday into next
Friday.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion
National Weather Service Phoenix AZ
230 AM MST SAT JUN 11 2016
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
As the larger synoptic scale ridge axis shifts into the southern
plains early this morning, several shortwaves/vorticity centers are
evident in satellite imagery streaming north on the western
periphery of this high pressure. The primary vorticity
center/easterly wave has already lifted near Las Vegas, however
several convectively induced MCV`s are still evident over NE AZ and
SE AZ within the debris cloud field. Meanwhile, a fuller latitude
trough in the westerly flow across the East Pacific was edging
towards the US West Coast, and effectively enveloping the local
forecast area under dryslot subsidence. This latter East Pacific
trough will slowly move across the SW Conus through early next week
and be the primary influence on weather and temperatures.
Through today, flow aloft will become more predominantly southwest
gradually scouring away moisture through horizontal advection and
vertical mixing. 00Z KTWC sounding data still sampled a daily record
1.49" PWAT, however 00Z KNKX data interrogated substantial drying in
the H8-H5 layer which will undoubtedly overspread the downstream
area (i.e. SE CA and AZ) through today. NAM Bufr forecast soundings
are still reluctant to fully relinquish the 10 g/kg boundary layer
moisture profiles in lower elevation locations this afternoon
resulting in a period of modest instability in a weakly capped
environment. Given trends in satellite and past events under similar
flow patterns, believe upslope regions over the Mogollon Rim and
White Mountains would be more favored for deep convection; and a
vast majority of high resolution models and ensemble systems support
this rational.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Isolated weak thunderstorms will nibble at the fringes of metro
Phoenix through 06Z but are not expected to reach any of the
terminals. However, weakening outflow from distant storms will lead
to development of easterly surface winds overspreading east Valley
beginning 05Z. May see a stray sprinkle/shower through 07Z but
otherwise debris clouds will thin out overnight. Anticipate
redevelopment of some thunderstorms over higher terrain east of
Phoenix after 18Z.
Southeast California/Southwest Arizona including KIPL and KBLH:
Upper level disturbance will exit southeast California overnight
leaving behind clearing skies. Before then, some isolated weak
showers will linger over/near Joshua Tree National Park through 08Z.
Surface winds will continue to favor south and southeasterly
directions but will be relatively light overnight before
strengthening during the afternoon (gusts to 20-30 kts).
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday...
As high pressure begins to build back over the region, dry air will
predominate with near normal temperatures Monday through Tuesday.
Warmer than average temperatures will arrive Wednesday and continue
for the remainder of the week. Minimum humidities in the upper
single digits to mid teens Monday will fall into the mid single
digit to low teen range by Thursday and Friday with fair overnight
recovery. Winds will remain mainly on the light side with afternoon
gustiness through the forecast period, following typical diurnal
trends.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...MO
AVIATION...AJ
FIRE WEATHER...Hernandez/Percha
Area Forecast Discussion
National Weather Service Flagstaff AZ
955 PM MST FRI JUN 10 2016
.SYNOPSIS...Expect numerous showers and thunderstorms over central
and western Arizona to slowly end overnight. Drier southwest flow
returns later on Saturday and Sunday, with breezy conditions and far
less shower activity. A chance of showers and thunderstorms returns
on Monday, before a strong warming and drying trend for the
remainder of next week.
&&
.DISCUSSION...A large area of convection formed this evening along
with eastern border of a mesoscale upper low moving north through
the Lower Colorado River Basin. This area is moving northwest and
propagating outflow boundaries to the west. Much higher PW air is
associated with this area of rainfall, with dewpoints over 50 in
many places. Many areas have reported up to an inch of rainfall.
The hardest hit locations are in northern Gila county and into
southern Coconino county.
As the upper low moves away from the area later tonight, the forcing
will weaken and drier southwest will replace the current airmass by
later Saturday and Sunday.
An upper level trough moving through the area will continue breezy
to windy conditions through the weekend. Enough cold air aloft may
accompany the trough passage by Monday for the formation of more
thunderstorms, albeit from a different mechanism and a different
moisture source.
The rest of next week will be hot and dry.
We have been updating most of the shift as we track this area of
convection, trends should be downward from here on out. No further
significant updates are anticipated.
&&
.AVIATION...For the 06Z Package...SCT SHRA/TSRA with isolated
MVFR +TSRA VRB30G40kts moving northwest at 15-20kts through
10Z...then Isold -shra/-tsra. Aviation discussion not updated for
TAF amendments.
&&
.FIRE WEATHER...Expect increasing high-based shower and thunderstorm
activity from southeast to northwest through the overnight hours.
Strong and erratic outflow winds are likely near storms. On
Saturday, lingering moisture will cause a round of scattered high-
based storms, primarily over higher terrain. Gusty southwest winds
and mainly dry conditions are expected on Sunday.
Monday through Wednesday...Slight chances for thunderstorms are
forecast Monday. Dry weather and a warming trend forecast Tuesday
and Wednesday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...Peterson
AVIATION...MAS
FIRE WEATHER...RR
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Phoenix AZ
954 PM MST FRI JUN 10 2016
.UPDATE...
Updated Aviation section.
&&
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather than the past week. A
temporary increase in moisture will support some showers and storms
over higher terrain of central and southern Arizona overnight and
Saturday. Temperatures near the seasonal average will continue
through early next week before hotter conditions become re-
established during the latter half of the week.
&&
.DISCUSSION...
Vort max centered over southeast CA this evening continues to track
northward. Despite the vorticity advection, only isolated weak
showers developed over southwest AZ and southeast CA earlier this
afternoon due to insufficient surface heating to break the CIN. Best
storm activity was over east-central and southeast AZ where CAPE was
better and CIN was breakable. Still ongoing activity as of this
writing over northern Gila and far northeast Maricopa County.
However, considerable CIN has kept storms out of most of the metro
area so far and that will likely be the case the rest of the night.
Held on to a low end slight chance over the lower elevations of
Maricopa County and Pinal County due to lingering CAPE and activity
over northern AZ (plus outflow from southern Gila Co.) Otherwise,
dropped PoPs elsewhere except over/near Joshua Tree National Park
close to the vort max center and where there have been lingering
echoes. Models show the vort max and convection to the east tracking
northward overnight. The dropoff in the model convection makes sense
given a southerly component to the steering flow and the fact that
things are quiet over southeast AZ. Held on to PoPs over zone 24 for
Saturday per model CAPE. Of note, both RAP and NAM12 have a batch of
CAPE that affects metro Phoenix but CIN values are a bit high.
&&
.Previous Discussion...issued 159 pm MST/PDT...
A brief introduction to the monsoon is expected this afternoon and
this evening across the desert southwest. Latest 12z sounding from
TWC sampled a record PWAT of 1.46 inches, while SPC mesoanalysis
indicates that even higher PWATS are concentrated across southern
Pima County associated with a well- defined vort max and 700 mb
inverted trough across northern Sonora.
Widespread canopy of high clouds from this low overspread much of
southern Arizona this morning. However, clouds have dissipated as
expected across eastern Arizona and congested CU has been quick to
develop across the higher terrain of southeastern AZ. Surface
dewpoints remain exceptionally high this afternoon across the lower
deserts, generally in the mid to upper 50s and have even increased
early this afternoon. Latest ACARS soundings out of KPHX show an
exceptionally moist profile with mixing ratios exceeding 10g/kg
through 750 mb. However, a strong subsidence inversion is also
evident, which will initially act to inhibit convection across the
Phoenix area. SPC mesoanalysis depicts MLCAPEs in excess of 1000 J/kg
across SE AZ, while the aforementioned CIN is strong and prevalent
from Phoenix northwestward through the lower Colorado River.
Southeasterly steering flow around 25 kt between the Four Corners
anticyclone and the inverted trough is also quite anomalous. General
consensus among the latest CAMs is that increasing instability and
convection across SE AZ will propagate northwestward, possibly
reaching eastern portions of the Phoenix area this evening. PoPs in
the latest raw and post-processed guidance have trended upward and
the forecast was adjusted accordingly, as high as 30 to 40 percent
across portions of Pinal and southern Gila counties. Typical
inverted-V soundings suggests a high probability of strong
downdrafts. There also remains a discernible threat for outflow
boundaries producing blowing dust and the Blowing Dust Advisory
remains in effect for Pinal and southern Maricopa counties through
this evening. Models remain in good agreement that the activity will
lift northward into northern AZ later this evening.
By Saturday, flow aloft becomes much stronger from the southwest
helping remove any convective debris, but also shearing any small
shortwaves and/or more pronounced divergence fields well away from
the forecast area. The deeper southwest flow will also aid in
mechanically removing moisture from the atmospheric column, though
NAM Bufr soundings strangely still show 10 g/kg and a weakly capped
environment Saturday afternoon. Feel better mixed GFS Bufr output
closer to 6 g/kg may be more accurate forcing most (if not all)
deeper convection in an upslope regime along the Rim and White
mountains. This stronger flow regime will also restrict the ability
of any outflow boundaries from traveling appreciably far from their
origination point.
Forecast models during the first half of next week remain in good
agreement that modest cold core troughing will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range. By
this time, any better quality moisture will have been repositioned
downstream of southeast California and Arizona and all evidence
points to dry weather (sans high terrain locations of eastern AZ).
However, the benefit will be temperatures in a near normal range
with highs in the upper 90s to lower 100s. Unfortunately as this
trough continues to propagate east, ridging will rebuild into the
area with H5 heights rebounding to a 588-594dm range yielding
afternoon highs back near 110F by the end of the week.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Isolated weak thunderstorms will nibble at the fringes of metro
Phoenix through 06Z but are not expected to reach any of the
terminals. However, weakening outflow from distant storms will lead
to development of easterly surface winds overspreading east Valley
beginning 05Z. May see a stray sprinkle/shower through 07Z but
otherwise debris clouds will thin out overnight. Anticipate
redevelopment of some thunderstorms over higher terrain east of
Phoenix after 18Z.
Southeast California/Southwest Arizona including KIPL and KBLH:
Upper level disturbance will exit southeast California overnight
leaving behind clearing skies. Before then, some isolated weak
showers will linger over/near Joshua Tree National Park through 08Z.
Surface winds will continue to favor south and sotheasterly
directions but will be relatively light overnight before
strengthening during the afternoon (gusts to 20-30 kts).
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Monday through Friday... As high pressure begins to build back over
the region, dry air will predominate with near normal temperatures
Monday through Tuesday. Warmer than average temperatures will arrive
Wednesday and continue for the remainder of the week. Minimum
humidities in the upper single digits to mid teens Monday will fall
into the mid single digit to low teen range by Thursday and Friday
with fair overnight recovery. Winds will remain mainly on the light
side with afternoon gustiness through the forecast period, following
typical diurnal trends.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...AJ
PREVIOUS DISCUSSION...Hirsch/MO
AVIATION...AJ
FIRE WEATHER...Hernandez/Percha
Area Forecast Discussion
National Weather Service Tucson AZ
330 PM MST SAT JUN 11 2016
.SYNOPSIS...Expect scattered showers and thunderstorms from Tucson
eastward into this evening. A few thunderstorms may occur near the
New Mexico border Sunday followed by dry conditons Monday through
Friday. Daytime temperatures will remain near normal or a few
degrees below normal through Tuesday, then hotter temperatures
return Wednesday through Friday.
&&
.DISCUSSION...Scattered showers and thunderstorms were ongoing
mostly north-to-east of the Tucson metro area this afternoon.
Various 11/12Z NWP models suggest the bulk of these showers and
thunderstorms will gradually decrease in coverage and intensity
during the next several hours. Expect isolated to scattered showers
and thunderstorms mainly from Tucson east to the New Mexico border
this evening. A slight chance of showers and thunderstorms then
continues late tonight into Sunday evening mainly near the New
Mexico border.
11/12Z GFS/ECMWF/CMC were similar with depicting a baggy upper
trough over the desert southwest Monday. Stronger swly flow aloft
Monday will push deeper moisture well newd into the central/srn
Rockies and adjacent high plains. Precip-free conditions will
commence Monday, and dry conditions will continue Tuesday into next
weekend as high pressure aloft gradually amplifies during the latter
part of the upcoming week. The GFS/ECMWF were quite similar with the
depiction of at least a 597 dm high to be centered over ern Arizona/
wrn New Mexico by next Saturday. The upshot...high temps thru Tue
will generally a few degs or so below normal, then hotter temps will
prevail Fri-Sat.
&&
.AVIATION...VALID THRU 12/18Z.
Isolated to scattered TSRA/SHRA from KTUS vicinity nwd/ewd into this
evening, then isolated -TSRA/-SHRA mainly near the New Mexico border
late tonight thru Sunday afternoon. Brief wind gusts to around 45
kts will occur with the stronger thunderstorms. Otherwise, cloud
decks from Tucson eastward will range from 7k-10k ft msl. Clear
skies or scattered clouds above 15k ft msl west of KTUS into Sunday
morning. Surface wind this afternoon wly/swly at 12-18 kts with
gusts to 25 kts. Surface wind mainly less than 10 kts at other times
except near thunderstorms. Aviation discussion not updated for TAF
ammendments.
&&
.FIRE WEATHER...Expect scattered thunderstorms into this evening,
especially from Tucson northward, and eastward to the New Mexico
border. Isolated thunderstorms Sunday afternoon will occur mostly
near the New Mexico border. Dry conditions will then prevail Monday
through next Saturday. Daytime temperatures will be a few degrees
below normal into early next week, then hotter temperatures return
Wednesday into next weekend.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
[top]
Area Forecast Discussion...UPDATED
National Weather Service Flagstaff AZ
323 PM MST SAT JUN 11 2016
.SYNOPSIS...Isolated to scattered thunderstorms will continue over
northern Yavapai and western Coconino counties through the late
afternoon hours. Dry and breezy conditions are forecast Sunday,
with a slight chance of thunderstorms north of I-40 Monday. A
drying/warming trend will commence Tuesday, and will continue
through the end of next weekend.
&&
.DISCUSSION...Isolated to scattered thunderstorms continue to
develop over northern Yavapai and western Coconino counties where
MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep
layer shear is keeping this convection disorganized and well below
severe limits. This activity should continue through the late
afternoon hours, then begin to wane around sunset with the loss of
daytime heating.
By Sunday, an upper level trough will sag just west of the Baja
Peninsula. Models prog Arizona to get dry slotted with little to no
convection anticipated. However, given the proximity of the trough
and subsequent height gradient, breezy to windy conditions are
forecast over northern Arizona. Winds should remain below advisory
levels.
Monday, the aforementioned trough will weaken as it lifts north over
Arizona. The best upper forcing should remain confined to areas
north of I-40. Upper dynamics (albeit weak) combined with lingering
moisture and instability should be sufficient to warrant a slight
chance of Monday afternoon thunderstorms north of I-40.
Tuesday through Saturday, an upper level ridge will build over the
southwestern United States. This will lead to a drying and warming
trend over Arizona through next weekend (June 19).
&&
.AVIATION...For the 00Z Package...Southerly flow and lingering
moisture will allow for continued isolated to scattered showers and
thunderstorms for the rest of the afternoon. After 02Z showers and
thunderstorms will diminish. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...Showers and thunderstorms will diminish this
evening around sunset. On Sunday drier air moves in ending chances
for thunderstorm activity while southwest 20FT winds will increase
to a sustained 15 to 20 mph range. Monday a few isolated showers
possible along and north of Interstate 40.
Tuesday through Thursday...High pressure builds in from Tuesday
onward with hot and dry weather in the extended forecast.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...TM
AVIATION/FIRE WEATHER...Bohlin
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Flagstaff AZ
308 PM MST SAT JUN 11 2016
.SYNOPSIS...Isolated to scattered thunderstorms will continue over
northern Yavapai and western Coconino counties through the late
afternoon hours. Dry and breezy conditions are forecast Sunday, with
a slight chance of thunderstorms north of I-40 Monday. A
drying/warming trend will commence Tuesday, and will continue
through the end of next weekend (June 19).
&&
.DISCUSSION...Isolated to scattered thunderstorms continue to
develop over northern Yavapai and western Coconino counties where
MUCAPE values are ranging between 1000-1500 J/kg. However, weak deep
layer shear is keeping this convection disorganized and well below
severe limits. This activity should continue through the late
afternoon hours, then begin to wane around sunset with the loss of
daytime heating.
By Sunday, an upper level trough will sag just west of the Baja
Peninsula. Models prog Arizona to get dry slotted with little to no
convection anticipated. However, given the proximity of the trough
and subsequent height gradient, breezy to windy conditions are
forecast over northern Arizona. Winds should remain below advisory
levels.
Monday, the aforementioned trough will weaken as it lifts north over
Arizona. The best upper forcing should remain confined to areas
north of I-40. Upper dynamics (albeit weak) combined with lingering
moisture and instability should be sufficient to warrant a slight
chance of Monday afternoon thunderstorms north of I-40.
Tuesday through Saturday, an upper level ridge will build over the
southwestern United States. This will lead to a drying and warming
trend over Arizona through next weekend (June 19).
&&
.AVIATION...For the 00Z Package...Southerly flow and lingering
moisture will allow for continued isolated to scattered showers and
thunderstorms for the rest of the afternoon. After 02Z showers and
thunderstorms will diminish. Aviation discussion not updated for TAF
amendments.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...TM
AVIATION...Bohlin
For Northern Arizona weather information visit
weather.gov/flagstaff
[top]
Area Forecast Discussion
National Weather Service Phoenix AZ
224 PM MST SAT JUN 11 2016
.SYNOPSIS...
High pressure will be displaced to the east over the next several
days resulting in somewhat cooler weather through early next week.
Showers and thunderstorms will also be pushed well east as drier air
moves back into the region. After several relatively comfortable
days with near normal temperatures through the middle of next week,
excessively hot weather will likely settle back into the area by the
end of next week.
&&
.DISCUSSION...
As earlier thought, storm activity did form over portions of south-
central and southeast AZ over the last few hours...just not over the
Rim and White Mtns but the along the foothills/mountains across
Pinal/Maricopa/Pima Counties along I-8/I-10. SPC mesoanalysis,
Suominet PWV and TPW satellite imagery indicated the main PWAT
axis/concentration south of the Phoenix Metro and storms still
persist across portions of Pinal County at time of writing. South to
southwesterly steering flow aloft has lofted debris cirrus over the
Phoenix area and for the time being, stabilized the area enough to
prevent any northward advancement of the remaining isolated storms
over the open deserts to the south. Early afternoon IR imagery
depicts a clear boundary between the drier and better mixed portions
of far southwest AZ and southeast CA and the storms/debris clouds
over south-central AZ. Storms so far today managed to form in a
slight deformation zone aloft as flow further to the west begins to
turn ahead of an approaching upper trough and then splits over
central AZ with the expansive anticyclonic flow over the central
CONUS.
For the rest of this evening, still favorable mixed-layer CAPE
surface and upper difluence will allow for additional isolated storm
development east of the areas where storms formed so far today.
Cannot rule out a thundershower or two making their way northward
into the Phoenix-metro through 6pm or so, otherwise we`ll remain
under the debris cloudiness and occasional outflow driven breezes.
Conditions will continue to further mix out across the western
forecast zones as drier air is advected into the area with continued
breezy south winds. Activity should quickly dissipate after sunset
and loss of daytime heating, with clouds continuing to stream
north/northeastward before clearing out overnight.
Forecast models during the first half of next week remain in good
agreement that a modest cold core trough will pass through the
Southwest keeping H5 heights temporarily in a 580-588dm range.
Although dynamic forcing with this system looks to be ample, any
better quality moisture will have been repositioned downstream of
southeast California and Arizona. This should be true for the entire
atmospheric column, and little other than a brief frontal cloud band
would be anticipated. However, the benefit from this system will be
temperatures hovering in a near normal range with highs only in the
upper 90s to lower 100s.
Unfortunately, the western hemisphere flow pattern will become far
more blocked and amplified during the latter half of next week and
through the weekend. With mean negative height anomalies roughly
centered over the NE Pacific and northern Quebec, strong ridging
will build throughout the intermountain west. Not only is there
seasonal preference for this configuration, but essentially every
NAEFS member indicates an almost identical pattern yielding
excellent forecast confidence. The biggest question will be how warm
it gets as the 00Z operational GFS and handful of ensemble members
indicate H5 heights eclipsing the 600dm threshold over the four
corners next weekend. Regardless, NAEFS mean output for next weekend
already suggests heights/temperatures aloft in the 99th percentile,
and its not atypical for the warmer extreme parts of an ensemble
system to verify this time of year. Thus, its already a very good
bet that excessive heat and afternoon highs at least 115F will
return by the end of next week; and not out of the question if the
GFS type heights come to fruition that someone could be making a run
at the 120F mark sometime next weekend.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL; and Southeast
California/Southwest Arizona including KIPL and KBLH:
Isolated showers and thunderstorms should only impact areas south of
the Phoenix metro through the rest of the afternoon, but confidence
is not high enough to totally rule a shower or storm to briefly
affect southern portions of the metro area. Breezy southerly winds
will eventually turn westerly this evening for the Phoenix terminals
and remain westerly through much of the overnight. After midnight
the area will be under drying conditions and clearing skies. Gusty
southerly winds will affect southeast California including KBLH and
KIPL through around midnight with winds 10 kts or less thereafter.
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Tuesday through Saturday...
Dry air will dominate through the forecast period as high pressure
builds back over the region. As a result, minimum humidities over
the lower deserts will generally fall in the single digits each
afternoon. Temperatures will also be on the rise, with near normal
temperatures Tuesday, becoming warmer than average on Wednesday with
continued warming into the early part of the weekend. High
temperatures across the deserts will reach above 110 degrees
starting Saturday. Winds will generally be light, but afternoon
breeziness will be common with some gusts approaching 20 15 mph.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...Nolte/MO
AVIATION...Kuhlman
FIRE WEATHER...Kuhlman
Area Forecast Discussion
National Weather Service Flagstaff AZ
1218 PM MST SAT JUN 11 2016
.SYNOPSIS...Drier southwest flow returns later today and
especially Sunday, with breezy conditions and decreasing shower
activity. A chance of showers and thunderstorms continues on
Monday with a passing trough, before a strong warming and drying
trend for the remainder of next week.
&&
.UPDATE...Convection is firing over the higher terrain of Yavapai
county and western Coconino county early this afternoon.
Thunderstorm activity is also developing over southern Apache
county in the vicinity of the White Mountains. Think the
convection over Yavapai/western Coconino counties will expand in
coverage this afternoon due to increasing instability.
Updated the forecast to expand scattered coverage of afternoon thunderstorms
into the North Rim area based on current obs/trends. The remaining
weather elements are in good shape. The updated forecast has been
sent.
&&
.PREV DISCUSSION /346 AM MST/... Low pressure off the southern
California coast will approach Arizona over the coming days,
eventually crossing the state on Monday. In the meantime, chances
for showers will continue again today, though expected to be less
widespread than we experienced on Friday. Even less activity is
likely for Sunday, though gustier southwest winds are anticipated.
Monday appears to be our last chance for showers in the 7-day
forecast as the trough passes across the region. In the wake of
the passing trough, drier air and much warmer daytime temperatures
will return under strengthening high pressure.
&&
.AVIATION...For the 18Z Package...Southerly flow and lingering
moisture will allow for isolated to scattered showers and
thunderstorms today. Wind gust up to 35 kts possible with storms.
Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Expect showers and thunderstorms to develop this
afternoon with scattered coverage over Yavapai and western
Coconino counties. On Sunday drier air moves in ending chances
for thunderstorm activity.
Monday through Wednesday...A weak disturbance brings isolated
showers and a few thunderstorms to the northern third of the state.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...TM
AVIATION...Bohlin
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Flagstaff AZ
935 AM MST SAT JUN 11 2016
.SYNOPSIS...Drier southwest flow returns later today and
especially Sunday, with breezy conditions and decreasing shower
activity. A chance of showers and thunderstorms continues on
Monday with a passing trough, before a strong warming and drying
trend for the remainder of next week.
&&
.UPDATE...Current visible satellite imagery shows convective
clouds beginning to develop over Yavapai and western Coconino
counties. Furthermore, a mid/high level cloud deck over most of
Navajo and all of Apache counties should continue to lift north of
the region through the afternoon.
The latest high-res models prog increasing instability over
Yavapai and western Coconino counties today. Furthermore, with
dewpoints in the upper 40s and 50s, think enough lift and
instability should initiate convection along the Mogollon Rim this
afternoon. Weak deep layer shear should keep convection below
severe limits.
Updated the forecast based on current obs/trends. Increased the
temporal resolution of pops in order to try and best time the
convection across northern Arizona this afternoon. Otherwise, the
remaining forecast is on track. The updated products have been
sent.
&&
.PREV DISCUSSION /346 AM MST/... Low pressure off the southern
California coast will approach Arizona over the coming days,
eventually crossing the state on Monday. In the meantime, chances
for showers will continue again today, though expected to be less
widespread than we experienced on Friday. Even less activity is
likely for Sunday, though gustier southwest winds are anticipated.
Monday appears to be our last chance for showers in the 7-day
forecast as the trough passes across the region. In the wake of
the passing trough, drier air and much warmer daytime temperatures
will return under strengthening high pressure.
&&
.AVIATION...For the 18Z Package...Southerly flow and lingering
moisture will allow for isolated to scattered showers and
thunderstorms today. Wind gust up to 35 kts possible with storms.
Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Expect showers and thunderstorms to develop this
afternoon with isolated coverage in northwestern Arizona and more
scattered coverage in northeastern Arizona. On Sunday drier air
moves in ending chances for thunderstorm activity.
Monday through Wednesday...A weak disturbance brings isolated
showers and a few thunderstorms to the northern third of the state.
High pressure builds in from Tuesday onward with hot and dry weather.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...TM
AVIATION...Bohlin
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Tucson AZ
915 AM MST SAT JUN 11 2016
.SYNOPSIS...Expect scattered showers and thunderstorms from Tucson
eastward into this evening. A few thunderstorms may occur near the
New Mexico border Sunday followed by dry conditons Monday through
Friday. Daytime temperatures will remain near normal or a few
degrees below normal through Tuesday, then hotter temperatures
return Wednesday through Friday.
&&
.DISCUSSION...11/12Z Univ of AZ WRF-NAM and several HRRR solutions
suggest that showers/tstms will develop near the Tucson metro area
eastward/southward later this morning into early this afternoon.
These cells will then move quickly nwd/newd, with the main concern
for potentially damaging wind gusts. The bulk of these showers/
tstms will end this evening.
There are no updates planned at this time. Please refer to the
additional sections for further detail.
&&
.AVIATION...VALID THRU 12/18Z.
Isolated to scattered TSRA/SHRA from KTUS vicinity ewd/swd into this
evening, then isolated -TSRA/-SHRA mainly near the New Mexico border
late tonight into Sunday morning. Brief wind gusts to around 45 kts
will occur with the stronger thunderstorms. Otherwise, cloud decks
from Tucson eastward will range from 7k-10k ft msl. Clear skies or
scattered clouds above 15k ft msl west of KTUS into Sunday morning.
Surface wind this afternoon wly/swly at 12-18 kts with gusts to 25
kts. Surface wind mainly less than 10 kts at other times except near
thunderstorms. Aviation discussion not updated for TAF ammendments.
&&
.FIRE WEATHER...Expect scattered thunderstorms into this evening,
especially from Tucson east and south. Isolated thunderstorms Sunday
afternoon will occur mostly near the New Mexico border. Dry
conditions will then prevail Monday through Friday. Daytime
temperatures will be a few degrees below normal into early next
week, then hotter temperatures return Wednesday into next Friday.
&&
.PREV DISCUSSION /234 AM MST/...Precipitable water values remain
well above mid-June normals this morning with values mostly in the
1.00"-1.50" range. Water vapor imagery showed an upper level low
approaching southern CA. Drier air will start to push in from the
west as the day progresses, but enough will be around across the
eastern 2/3rds of the area for isolated valley/scattered mountains
showers and thunderstorms. Precipitable water values are forecast to
be below 1" on Sunday with a slight chance of storms relegated to
the White mountains. High temperatures this weekend will remain
several degrees below normal.
Upper level trof will push across the state on Monday providing
slightly cooler daytime temperatures and further drying of the
atmosphere.
Upper ridge strengthens over the area Tuesday through Friday
resulting in warmer daytime high temperatures.
Outside of this forecast package are likely hotter daytime
temperatures as the upper ridge continues to strengthen over the
area. Highs next weekend could rival what occurred earlier this
month.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
327 PM CDT SAT JUN 11 2016
.SHORT TERM...(This Evening through Sunday)
Issued at 325 PM CDT SAT JUN 11 2016
A weak MCV was moving across northwest Missouri this afternoon which
formed from an earlier MCS over Iowa this morning. Short term high
resolution models have been showing convection developing through
the morning and afternoon in northeast and east central Kansas.
Latest RUC soundings show a weak cap remaining in place through peak
heating. Cumulus remains rather flat across the area this afternoon
similar to previous afternoons. Upper level ridge remains in place
across the Central Plains. Tonight expect the cumulus clouds to
dissipate with the loss of heating with mostly clear skies expected.
Lows tonight will be similar to last night with low to mid 70s
common. Sunday models continue to show some mid level energy over
northeast Oklahoma and southeast Kansas. There may be enough lift in
the afternoon when atmosphere becomes uncapped for isolated
thunderstorms to develop from southeast Kansas into Arkansas and
will leave east central Kansas dry for now with model qpf
clustering to the southeast of the cwa. Highs on Sunday will be
similar to today with highs in the low to mid 90s. Heat indices
will again approach 100 degrees across parts of the area on Sunday
afternoon.
.LONG TERM...(Sunday Night through Saturday)
Issued at 325 PM CDT SAT JUN 11 2016
Sunday night through Tuesday, storm chances increase for much of the
period. Late Sunday evening have gone with slight chance POPs over
southern to western portions of the area as perhaps weak forcing may
provide enough lift in a moist environment to cause a few showers
and thunderstorms. The chance remains small at this point as the
boundary layer will remain mostly capped off and a weak upper
circulation advances into southern Missouri. Late Sunday, a storm
complex develops over west central Nebraska along the nose of a LLJ
and slowly works its way southeast into the forecast area by early
morning into a less favorably sheared environment and an area of
smaller scale shortwave ridging. During the day, remnant
thunderstorm activity and an uncapped environment should lead to
mostly cloudy conditions with a few thunderstorms possible over
eastern portions of the forecast area where weak ridging will still
be influencing the area but continuing to be suppressed as larger
scale forcing advances from the west. Therefore, have left chance
POPs over western portions of the forecast area into the afternoon
on Monday.
Tuesday night, a LLJ will likely aid in the development
of thunderstorms over western KS and as storms grow upscale, another
complex may develop and begin to advance into the north central
Kansas and on into northeastern Kansas over night. Most long term
guidance is generally in better agreement but still details seem to
be in question such as exact positioning of the upper wave and
strength of the upper wave as it moves out of the Central Rockies
into the Central Plains. Previous runs have shown this wave to
actually be a closed off low and more intense but that has been
backed off at this point a bit and now the overall flow of the
southern stream energy may be a bit weaker. Regardless, a more
northerly track of the upper low seems to make sense based on
current positioning just off the SoCal region. Depending on the
actual strength of the upper trough feature, it seems to make sense
that as the overnight MCS organizes out west and moves into western
portions of the forecast area it could be sustained through the
morning into the early afternoon hours as shear profiles increase to
above 35kts, MUCAPE reaches to around 2,000 to 2,500 J/kg and mid-
level lapse rates increase to at least conditional and probably up
to around 7 C/km. Of course, some changes will likely occur between
now and Tuesday as to how much severe potential we end up with, but
at least some needed rain will likely fall over much of the area as
the long term forecast looks mainly dry after this round of precip
with possibly the exception of next Friday time frame as a
frontogenetical response sets up on the backside of the wave
previously mentioned as it transitions into a cut-off low eventually
working back into portions of the Ohio and mid MS Valley regions
before filling and transitioning into a frontal system over the East
coast region. Temps cool back a bit into the mid and upper 80s by
next weekend as more zonal flow sets up over the Northern into
Central Plains.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1122 AM CDT SAT JUN 11 2016
VFR conditions are expected throughout the period. Short term
guidance hints at the possibility for an isolated thunderstorm
this afternoon. Did not include VCTS as confidence is very low in
development, but will continue to monitor.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Drake
AVIATION...Baerg