Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/18/16
Area Forecast Discussion
National Weather Service Phoenix AZ
845 PM MST SUN JUL 17 2016
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Although we did finally see a return to more southerly flow aloft,
and a increase in mid-level moisture over south-central AZ,
convective activity has turned out to be virtually nonexistent over
our cwa this so far this afternoon/evening. The primary reason for
the lack of convection is likely due to the fact that a considerable
amount of debris cloudiness from thunderstorms over southeast
AZ/northern Mexico lingered over the region well into Sunday
afternoon, which limited daytime heating, with high only getting
into the upper 90-low 100 range over the lower deserts. The latest
high-res HRRR and RAP13 model runs are now showing more debris
clouds from storms, that are now firing over southeast AZ and along
the international border, moving northward across our cwa later
tonight and Monday morning, perhaps leading to a repeat of what we
saw today, with a cloudy morning once again limiting convective
development in the afternoon/evening. Thus, for the short term, have
reduced pops into the slight chance range for the rest of this
evening across the lower deserts of south-central AZ, and made some
minor adjustments to the hourly temp/wind/dewpoint grids.
&&
.PREVIOUS DISCUSSION...
Tonight...
A fairly complicated pattern with regards to precipitation in south
central AZ will develop later this afternoon and evening. It seems
that mid level disturbances are flying off the shelf so to speak,
and into southern AZ. One feature was noted this morning in weather
balloon data and later with sunlight, visible satellite imagery.
This feature was responsible for increased thunderstorm activity
between Gila Bend and the Mexican border at noon. Then there is
another large mid level circulation feature in northwest Mexico (an
MCV from last nights Sonora Mex convection) that is forecast by the
models to move into AZ just west of Tucson by 5 pm MST. The GFS
model is forecasting a couple of Omega field 500-300 mb bullseye
areas from Pinal County just north to Tucson, to portions of south
Central AZ just north of the Mexican Border this evening.
Therefore with increased moisture, and a couple of nearby dynamical
features, it would be best to increase chances for showers and
thunderstorms over our south central AZ zones, with the best chances
southwest and south of Phoenix. Diminishing showers are expected
after midnight partial clearing skies.
Monday...Much higher monsoon moisture will have spread over the
region by Monday afternoon. With the lack of any notable mid/upper
level disturbances, we will go with a standard low grade monsoon
forecast, i.e. slight chance of afternoon and evening thunderstorms
especially mountains east of Phoenix.
Tuesday...The easterly wave moving out of west Texas this evening
(Sunday) and into Chihuahua and Sonora Mexico is progged by the GFS
model to bodily move into southern Arizona by late Tuesday afternoon
and night. We have elevated the threat of precip slightly in south
central AZ Tuesday evening because of this feature.
Wednesday...Monsoon moisture will be still be entrenched over the
region. Again without any mid/upper level disturbances expected,
only a slight chance of showers and thunderstorms are forecast for
south central AZ.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will flatline at the
114 degree mark. Ouch!
&&
.AVIATION...
The lack of convective activity this evening over south-central AZ
means that the typical shift to easterly winds will likely not take
place until later tonight. We still could also see residual leftover
showers passing through Phoenix later tonight and on Monday morning
as leftover debris clouds from this evening`s crop of thunderstorms
over southeast AZ/NW Mexico once again move across the region,
though shower intensity would most likely be light and impacts
minimal. Some clearing is likely by early Monday afternoon. There is
once again a slight chance for thunderstorms during the late
afternoon/early evening hours on Monday, but confidence is too low
to include in the tafs at this time.
Southeast California/Southwest Arizona including KIPL and KBLH:
Only moderate confidence in terminal forecasts through Monday
morning as thicker 15K-20K cigs spread into SE CA. While
virga/sprinkles may occur briefly, any thunderstorm activity should
remain well east of the area. Sfc winds will favor a southerly
direction (occasionally gusty at KBLH) and southeasterly at KIPL,
though a brief period of evening SW winds at KIPL will be possible
on Monday.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Wednesday through Sunday...
Moisture and relative humidity values will decrease very slightly
through the latter half of the week as high pressure tends to
strengthen and air temperatures climb back to into an above normal
range. Thunderstorm and wetting rain potential will generally be
limited to higher terrain locations north and east of Phoenix, with
better potential for outflow winds heading downhill into lower
elevations of central Arizona. Minimum relative humidity values in a
15 to 25 percent range during the middle of the week will fall to a
10 to 20 percent range by the end of the week. Overnight recovery
will be fair to good. Outside of winds near thunderstorms,
directions will favor an upslope component in the afternoon with
typical gustiness and light overnight drainage.
$$
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...Percha/Vasquez
AVIATION...Percha/MO
FIRE WEATHER...MO
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
325 PM CDT SAT JUL 16 2016
.SHORT TERM...(This Evening through Sunday)
Issued at 323 PM CDT SAT JUL 16 2016
At 20Z, WV imagery shows a complex of storms off over the Dakotas
moving east/southeast into the Upper MS Valley. Meanwhile a another
upper level low pressure system and associated shortwave continues
to work into eastern MT. Further south, a plume of mid to upper
level moisture can be seen streaming through the Central Rockies
into Nebraska. Subtle shortwaves continue to work through this
region. At the surface, an area of low pressure is over
northeastern CO vicinity with a warm boundary stretched along and
near the KS/NE border.
Most of the severe activity today should remain north of the outlook
area and be associated with the two northern systems. However, there
is a small chance that storms develop this afternoon and evening
over northeastern CO and southwestern NE before organizing into a
small MCS that could potentially propagate into north central and
northeastern KS mainly along the KS/NE border late tonight into
early Sunday morning. A LLJ is expected to develop late this
evening and veer into the area by early morning. This should help
provide instability and convergence needed to keep at least some
storms going as they move into the area. The likely threat when
they arrive would be some strong gusty winds.
For the day Sunday, clearing should continue over northern areas of
the CWA. As heights continue to rise throughout the day, do expect
that some areas could begin to approach heat advisory levels with
high temps over northeast Kansas pushing into upper 90s and some
100s over southwestern counties into north central Kansas. Headline
may need to be issued by overnight shift but will hold for now.
.LONG TERM...(Sunday Night through Saturday)
Issued at 323 PM CDT SAT JUL 16 2016
Sunday Night through Tuesday...
Frontal boundary is expected to move into north central and
northeast Kansas Sunday night. Low level jet increases through the
evening then veers to near westerly by monday morning. There is not
much in the way of convergence along the front across northeast
Kansas and looks to focus to the northeast of the forecast area.
Therefore will leave small pops across the northern CWA north of
Interstate 70 Sunday night into Monday morning. Have kept small pops
going for areas north of Interstate 70 with the northeast return of
the frontal boundary Monday night into Tuesday morning. Lows Sunday
night will be in the low to mid 70s. Temperatures warm back into the
upper 90s near central Kansas on Monday with lower 90s near the
Nebraska border. Heat indices on Monday look to be in the 98 to 104
degree range. By Tuesday expect temperatures to warm into the mid
and upper 90s once again with afternoon heat indices in the 100 to
103 degree range.
Tuesday Night through Saturday...
Mid-level ridging will be in place across the Central Plains for the
majority of the period. Good agreement amongst the EC and GFS with
the stout ridge overhead through Thursday. High temperatures will
soar into the middle 90s to perhaps 100 degrees Tuesday through
Thursday. Plentiful boundary layer moisture will contribute to upper
60 to lower 70 degree dewpoints. This combination of heat and
humidity will result in heat indicies in the 100 to 110 degree range
Tuesday through Thursday. These very hot and humid conditions may
continue into the weekend, however model agreement diverges for
Friday and Saturday. Both models have a trough across the Northern
Plains, however it`s effects on the forecast area differ. The GFS
shifts the ridge axis across the Rockies and sweeps a weak cold
front through the area. While the EC, keeps the frontal boundary
well north of the area, allowing the heat wave to continue.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1238 PM CDT SAT JUL 16 2016
For the 18Z TAFs, chances of showers or storms making it into the
terminals overnight remains too low to mention. The higher impact
to aviation likely coming in the form of an increasing LLJ between
07-14Z time frame which should veer over the region from the
southwest up to the mid 40kt range. Otherwise, aviation impacts
seem small for the time frame.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Drake
LONG TERM...Baerg/53
AVIATION...Drake
Area Forecast Discussion
National Weather Service Wichita KS
229 PM CDT SAT JUL 16 2016
.SHORT TERM...(This evening through Tuesday night)
Issued at 223 PM CDT Sat Jul 16 2016
Energy from a Northern Intermountain region upper trough will
weaken tonight through Sunday, with some of it being absorbed by
an upper trough swinging southeast through Manitoba into the Great
Lakes. A lee trough will strengthen some through this evening. A
weak cold front will then progress southeastward into the Central
Plains Sunday, stalling late Sunday into monday from southern Iowa
southwestward into northwestern Kansas.
Scattered storms should initiate near the lee trough axis by early
this evening from far western Nebraska into northeast Colorado, with
an eastward propagation overnight fed by a southerly 50 knot low-
level jet. This activity should occur mainly just north of the
warmest mid-level temperatures with storm chances mainly north of
Interstate 70 tonight. A low-level thermal ridge axis and mixing
will intensify northeastward across southwest into north-central
portions of Kansas Sunday ahead of the stalled front. This
combined with sunshine will allow highs to climb into the mid 90s
in southeast KS to around 100 degrees in the central part of the
state. Storms may develop over the central High Plains late
Sunday, moving eastward Sunday night to the north of the stalled
front. Once again, most or all of this convection should be
confined to near and north of Interstate 70 in central Kansas.
A mid-upper high will build over the south-central Plains region
Monday into Tuesday, with the stalled front lifting gradually north
of Kansas. This will result in mostly clear skies with hot weather
both days. Peak afternoon heat indices are projected in the 100-105
degree range Sunday through Tuesday.
.LONG TERM...(Wednesday through Saturday)
Issued at 223 PM CDT Sat Jul 16 2016
A 597-598 dam upper high center is progged to remain over the south-
central Plains during this extended forecast period. This will make
heat the main forecast concern, with daily highs from the mid 90s to
102 degrees (warmest central/south-central KS). Depending on how
much surface dewpoints can mix out, heat headlines are a
possibility. Do not see any good, consistent model signals to
insert rain chances into the forecast at this juncture.
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1220 PM CDT Sat Jul 16 2016
VFR conditions will dominate the region this afternoon. Winds
will be out of the South and gusty this afternoon. Wind will die
down some overnight but winds aloft will be a little higher. Otherwise,
VFR conditions will dominate overnight and tomorrow.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 74 98 75 97 / 10 0 10 10
Hutchinson 73 99 74 97 / 10 10 10 10
Newton 73 97 73 96 / 10 10 10 10
ElDorado 73 96 74 95 / 10 0 10 10
Winfield-KWLD 74 96 75 96 / 10 0 0 0
Russell 73 100 72 96 / 10 10 20 20
Great Bend 73 101 73 98 / 10 10 10 10
Salina 74 101 74 97 / 10 10 10 10
McPherson 73 97 73 97 / 10 10 10 10
Coffeyville 74 94 75 95 / 10 0 0 0
Chanute 73 94 74 94 / 10 0 10 10
Iola 73 94 74 94 / 10 10 10 10
Parsons-KPPF 73 93 74 94 / 10 0 10 10
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...ELM
Area Forecast Discussion
National Weather Service Wichita KS
229 PM CDT SAT JUL 16 2016
.SHORT TERM...(This evening through Tuesday night)
Issued at 223 PM CDT Sat Jul 16 2016
Energy from a Northern Intermountain region upper trough will
weaken tonight through Sunday, with some of it being absorbed by
an upper trough swinging southeast through Manitoba into the Great
Lakes. A lee trough will strengthen some through this evening. A
weak cold front will then progress southeastward into the Central
Plains Sunday, stalling late Sunday into monday from southern Iowa
southwestward into northwestern Kansas.
Scattered storms should initiate near the lee trough axis by early
this evening from far western Nebraska into northeast Colorado, with
an eastward propagation overnight fed by a southerly 50 knot low-
level jet. This activity should occur mainly just north of the
warmest mid-level temperatures with storm chances mainly north of
Interstate 70 tonight. A low-level thermal ridge axis and mixing
will intensify northeastward across southwest into north-central
portions of Kansas Sunday ahead of the stalled front. This
combined with sunshine will allow highs to climb into the mid 90s
in southeast KS to around 100 degrees in the central part of the
state. Storms may develop over the central High Plains late
Sunday, moving eastward Sunday night to the north of the stalled
front. Once again, most or all of this convection should be
confined to near and north of Interstate 70 in central Kansas.
A mid-upper high will build over the south-central Plains region
Monday into Tuesday, with the stalled front lifting gradually north
of Kansas. This will result in mostly clear skies with hot weather
both days. Peak afternoon heat indices are projected in the 100-105
degree range Sunday through Tuesday.
.LONG TERM...(Wednesday through Saturday)
Issued at 223 PM CDT Sat Jul 16 2016
A 597-598 dam upper high center is progged to remain over the south-
central Plains during this extended forecast period. This will make
heat the main forecast concern, with daily highs from the mid 90s to
102 degrees (warmest central/south-central KS). Depending on how
much surface dewpoints can mix out, heat headlines are a
possibility. Do not see any good, consistent model signals to
insert rain chances into the forecast at this juncture.
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1220 PM CDT Sat Jul 16 2016
VFR conditions will dominate the region this afternoon. Winds
will be out of the South and gusty this afternoon. Wind will die
down some overnight but winds aloft will be a little higher. Otherwise,
VFR conditions will dominate overnight and tomorrow.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 74 98 75 97 / 10 0 10 10
Hutchinson 73 99 74 97 / 10 10 10 10
Newton 73 97 73 96 / 10 10 10 10
ElDorado 73 96 74 95 / 10 0 10 10
Winfield-KWLD 74 96 75 96 / 10 0 0 0
Russell 73 100 72 96 / 10 10 20 20
Great Bend 73 101 73 98 / 10 10 10 10
Salina 74 101 74 97 / 10 10 10 10
McPherson 73 97 73 97 / 10 10 10 10
Coffeyville 74 94 75 95 / 10 0 0 0
Chanute 73 94 74 94 / 10 0 10 10
Iola 73 94 74 94 / 10 10 10 10
Parsons-KPPF 73 93 74 94 / 10 0 10 10
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...ELM
Area Forecast Discussion
National Weather Service Dodge City KS
215 PM CDT SAT JUL 16 2016
...Updated Long Term...
.SHORT TERM...(This evening through Sunday)
Issued at 1226 PM CDT Sat Jul 16 2016
Much quieter weather pattern unfolding for SW Kansas. A virtually
clear sky early this afternoon. S/SE winds will become strong and
gusty this afternoon, in response to a 994 mb surface low near
Limon, Colorado and about a 10 mb surface pressure gradient
between Syracuse and Kiowa. Some gusts of 30-35 mph will be noted.
12z NAM and HRRR model runs, which did an excellent job
forecasting last night`s thunderstorms, both keep tonight`s
expected MCS activity mainly north of SW Kansas, across NW Kansas
into Nebraska. Kept a slight chance of convection for northern
Ellis county through tonight, as that zone will be closest to the
Nebraska convection, but am not expecting much. A strong
pronounced low level jet is progged by all models to develop after
sunset, with 850 mb winds as high as 60 kts. As such, south winds
will remain quite elevated all night. This, in turn, will keep
temperatures quite elevated, with most locales only falling to the
lower 70s Sunday morning.
Sunday...Mostly sunny and hot. Strong upper high begins to build
strongly into the plains, with 500 mb heights rising sharply from
590 dm Saturday, to 594 dm Sunday afternoon. Afternoon
temperatures will be hotter in response, but not as hot as some
guidance indicates. Lack of downslope, the upper high organizing
east of SW KS near the Ozarks, and most importantly, lush
vegetation and standing water from recent rainfall...will all slow
down the heating trend. GFS/MAV/MEX guidance in the 100s is too
hot for Sunday. Forecasted upper 90s for most zones, and wouldn`t
be surprised if I am still several degrees too warm. NAM/ECMWF
both suggest perhaps an isolated thunderstorm across the far W/NW
zones late Sunday afternoon, but with weak shear and warming
temperatures aloft, am not expecting much.
.LONG TERM...(Sunday night through Saturday)
Issued at 215 PM CDT Sat Jul 16 2016
An extended stretch of typical summer weather...hot and dry...
will begin on Monday, and persist into next weekend. Little if any
day-to-day variation expected. Hot upper anticyclone establishes
near the Ozarks on Monday, and wallows around the southern plains,
slowly inching westward, ending up as a 598 dm upper high over SW
KS by Saturday. Afternoon temperatures will be in the mid to upper
90s for most locales through Wednesday. Starting about Thursday,
the topsoil will have dried enough, and the subsidence from the
upper ridge will have gotten close enough, to allow for widespread
triple digit heat. Morning low temperatures will hold in the low
to mid 70s for all locations. Rain/thunderstorm chances in this
pattern are remote, but not completely zero. Medium range models
suggest an isolated storm may clip the far W/NW zones during the
peak heating hours, farthest from the high pressure ridge`s
influence. Purposely kept all pop grids at slight chance (<25%)
with no significant rainfall expected.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1226 PM CDT Sat Jul 16 2016
Airports expected to remain free of thunderstorms through this
evening. Perhaps an isolated -TSRA west of GCK this afternoon, and
TSRA appear likely north of HYS tonight, but kept any mention of
convection out of the 18z TAFs. Strong S/SE winds will impact
aviation operations this afternoon, gusting over 30 kts at times,
in response to 994 mb surface low near Limon Colorado. A strong
pronounced low level jet is forecasted tonight, with NAM
forecasting 850 mb winds near 60 kts. Expect southerly winds to
remain elevated overnight, along with widespread low level wind
shear.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 94 74 98 70 / 10 10 10 10
GCK 95 71 97 69 / 10 10 10 10
EHA 97 71 100 71 / 10 10 10 10
LBL 93 72 101 71 / 10 0 10 10
HYS 91 72 97 71 / 10 20 10 20
P28 95 75 100 73 / 10 10 0 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Turner
LONG TERM...Turner
AVIATION...Turner
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1245 PM CDT SAT JUL 16 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 301 AM CDT SAT JUL 16 2016
Isentropic lift on the 310-320 K surfaces should begin to increase
in the next few hours over central KS. Expect that scattered showers
and storms will develop over central KS and move to the east
northeast through the late morning hours. The NAM is the aggressive
with keeping the lift across the forecast area through the early
afternoon. Consensus is that the instability this morning will be
around 1000-2000 j/kg and given the convection will be elevated the
shear will be limited. Therefore expect that these storms will stay
below severe limits. All of this is in to response of a weak front
stretched across central KS. A surface low pressure will deepen over
northeast CO later today, which will lift the front into southwest
NE. Soundings show that an elevated mix layer builds over the area
this afternoon, which should prevent any surface based convection.
Current water vapor shows an on going MCS in southeast MT supported
by a mid level shortwave. This wave will track over the northern
plains later today, and should initiate convection in SD, while
additional development is possible near the surface low pressure in
western NE. These clusters of storms could develop into several MCSs
that will move east southeastward during the evening hours. The low
level jet is forecasted to increase during this time frame, and may
support an MCS to move into portions of northeast KS, and or may
initiate additional convection over any existing cold pools across
eastern NE. There will be plenty of instability across the forecast
area, and sufficient shear needed to sustain a balanced cold pool
with the environment. As of now the most most likely track for an
MCS will be eastern NE and western IA. Any MCS will pose a risk for
damaging wind especially for areas along and north of I-70 through
the overnight.
.LONG TERM...(Sunday through Friday)
Issued at 301 AM CDT SAT JUL 16 2016
Frontal boundary sagging southward out of the northern plains into
western Kansas by late Sunday afternoon slows to a near stop through
the overnight hours into early Monday. Stronger flow to the north
and overnight LLJ also focus better chances north of the area late
Sunday night into early Monday. Initial impacts on temperatures
will be for a warm boost on Sunday as the mid level thermal ridge
ahead of the front rises into northeast Kansas, and have highs
from the lower 90s far northeast to near 102 out in central
Kansas, with overnight lows holding generally in the low 70s west
to middle 70s east. Could get a break with some cool outflow from
storms to the northeast. Have only kept low PoPs for early Sunday
and again in the overnight hours as think most storms will stay
north and east. Surface high advances farther south and east into
Monday, as upper flow takes a shift to the west northwest. This
could give one last day in the low to middle 90s before
temperatures ramp up for the week. Some models generating very
light QPF for Monday, but outside the boundary to focus on, not
seeing a strong source of lift and have just kept a slight chance
near or north of the front on Monday.
Northeasterly return of the 850mb front brings warm advection over
eastern Kansas Monday night, and have slight to chance for precip
mainly north of I70, pivoting over the eastern counties through
Tuesday afternoon. Temperatures rise out west back to upper 90s,
spreading into the eastern counties by Wednesday afternoon. Many
locations expected to see the century mark for Thursday and Friday
as the center of the upper high shifts over southern Kansas.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1238 PM CDT SAT JUL 16 2016
For the 18Z TAFs, chances of showers or storms making it into the
terminals overnight remains too low to mention. The higher impact
to aviation likely coming in the form of an increasing LLJ between
07-14Z time frame which should veer over the region from the
southwest up to the mid 40kt range. Otherwise, aviation impacts
seem small for the time frame.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Drake
Area Forecast Discussion
National Weather Service Goodland KS
1140 AM MDT SAT JUL 16 2016
.UPDATE...
Issued at 1135 AM MDT Sat Jul 16 2016
Main weather impact today will be thunderstorm development later
this afternoon. Convection models [HRRR/NMM] as well as NAM/RAP
indicate storms should develop over northeast Colorado after 21Z
and move ENE across extreme northern Kansas and southern Nebraska
this evening. NAM shows a lot of CINH through the day over all
but Colorado, so the scenario of formation there seems plausible.
While convection models keep precip on the scattered side, the NAM
hints at a more organized complex along NE/KS border by 9pm-
midnight which could throw down a decent cold pool and associated
outflow over northern half of the CWA tonight. Have tailored
forecast to keep precip in northern counties this evening, mostly
north of Highway 36.
On Sunday, guidance suggests a weak cold front will move through
the CWA in the morning with moist upslope flow behind it by
afternoon, which should assist in storm development over Colorado
during the afternoon ultimately moving into western Kansas.
&&
.SHORT TERM...(Today and Monday Night)
Issued at 307 AM MDT Sat Jul 16 2016
Latest upper air analysis shows northwest flow over the plains with
an upper level ridge axis to the west. Multiple small scale short
wave troughs were in the flow around the ridge to the west.
Today through Monday the weather pattern will continue to be active
as numerous upper level short wave troughs move across the Tri-State
Area bringing chances for rain with them.
This morning there may be some lingering thunderstorms east of
Highway 83 ahead of an upper level short wave trough. These storms
will be east of the area by mid morning if they do develop. Any
patchy fog that developed around sunrise will be gone by mid morning
too.
During the afternoon the cold front that moved through the area
yesterday will move back north as a warm front. Meanwhile an upper
level short wave trough will move across the northern part of the
Tri-State Area north of the warm front. With lower CINH ahead of
the warm front and lower dew point depressions at the LCL, am
expecting isolated to scattered storms to develop north of Highway
36. Most of the storm activity will be north of the area. Behind
the front the warmer air mass will allow the breezy low level jet to
mix to the ground, producing winds similar to yesterday or a bit
stronger.
During the afternoon the surface low in East Central Colorado will
push the dry line to the KS/CO border. However the dry line will be
behind the warm front in the drier more stable air so am not
expecting any storm development along the dry line as a result.
Strong to severe storms are expected north of the warm front this
afternoon into the early evening. Large hail up to baseball size
will be possible with the strongest storms. Damaging winds will
also be possible. There may be a threat for tornadoes north of the
warm front. However am not sure if the 0-1km shear will be strong
enough to support tornadic development north of the front.
This evening the upper level short wave trough will continue to move
across the northern part of the area. Meanwhile the front will
continue northward and briefly stall over the northern border of the
area during the overnight hours. By this time the short wave trough
and associated storm activity will be east of the area. Before
sunrise the front will be pushed back south as a cold front.
Sunday morning the cold front will stall along the southeast and the
western border. During the day the upper level flow will be
laminar. Toward evening an upper level short wave trough will move
over East Central Colorado from the west. Am expecting storms to
fire off the dry line along the western border of the Tri-State
Area. The storms should remain over East Central Colorado since the
lift from the upper level short wave trough will not extend very far
across the CO state line if at all.
During the evening the short wave trough will progress across the
Tri-State Area. Soundings show the majority of the low dew point
depressions to be above 600mb, so am not expecting there to be very
much storm coverage as the short wave trough moves across the area.
Monday the warm front will move back north to roughly Highway 24.
Behind the front drier, warmer air will move into the southern half
of the Tri-State Area. A few upper level short wave troughs will
move across the area during the day. However most of the low dew
point depressions will be in the mid and upper levels of the
environment. If any precipitation does occur am thinking it will be
from elevated showers associated with the passage of these short
wave troughs. There may be enough CAPE for a thunderstorm or two to
develop.
Monday evening a stronger upper level short wave trough will move
across the Tri-State Area. The front will move north of the Tri-
State Area by midnight. Meanwhile mid and upper level dew points
will increase as well leading to a better chance for storms to
develop with the trough passage. Storms may train along the front as
the front moves northward. This may lead to training thunderstorms
along the front. The storm activity will end from west to east
across the Tri-State Area during the overnight hours as the short
wave trough exits the area.
.LONG TERM...(Tuesday through Friday)
Issued at 307 AM MDT Sat Jul 16 2016
Tuesday through Friday shows strong ridging over the central CONUS.
For the most part the GFS and European agree on upper and mid level
patterns in the beginning of the period. Each day has potential
precipitation chances via the GFS, the European is a little drier at
times. Due to the slight differences between the two models slight
PoPs were included the days where a stronger signal was prevalent in
either model. The days precipitation chances are possible (primarily
Thursday and Friday) the moisture will move up into the CWA from
Arizona and the Gulf of California. As the end of the long term
period approaches the models start to differ slightly in upper level
pattern. The GFS has ridging over the western portion of the CONUS
and weak troughing in the east; that pattern is the primary driving
factor for precipitation chances. The European on the other hand has
the ridge more east (more over the central CONUS) and amplified than
the GFS; which explains the drier signal. Overall, this pattern will
limit moisture and PoP chances until the ridge weakens or moves
east. Do to the strength of the ridge, temperatures will be in the
upper 90s to low 100s in the beginning of the period. The latter
half of the period could see slightly cooler temperatures if the GFS
holds true, which is what is currently forecasted.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1140 AM MDT Sat Jul 16 2016
VFR at KGLD through the period. Thunderstorm development this
afternoon is expected to remain well northwest and north of the
terminal. Low level wind shear will develop after 02Z as a strong
low level jet develops around sunset.
At KMCK, VFR this afternoon into early evening. Thunderstorms are
forecast to develop over northeast Colorado late this afternoon
and eventually track across southern Nebraska approaching the
terminal in the 02-06Z time frame with gusty winds and MVFR
ceilings.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DLF
SHORT TERM...JTL
LONG TERM...CLT
AVIATION...DLF
Area Forecast Discussion
National Weather Service Goodland KS
1140 AM MDT SAT JUL 16 2016
.UPDATE...
Issued at 1135 AM MDT Sat Jul 16 2016
Main weather impact today will be thunderstorm development later
this afternoon. Convection models [HRRR/NMM] as well as NAM/RAP
indicate storms should develop over northeast Colorado after 21Z
and move ENE across extreme northern Kansas and southern Nebraska
this evening. NAM shows a lot of CINH through the day over all
but Colorado, so the scenario of formation there seems plausible.
While convection models keep precip on the scattered side, the NAM
hints at a more organized complex along NE/KS border by 9pm-
midnight which could throw down a decent cold pool and associated
outflow over northern half of the CWA tonight. Have tailored
forecast to keep precip in northern counties this evening, mostly
north of Highway 36.
On Sunday, guidance suggests a weak cold front will move through
the CWA in the morning with moist upslope flow behind it by
afternoon, which should assist in storm development over Colorado
during the afternoon ultimately moving into western Kansas.
&&
.SHORT TERM...(Today and Monday Night)
Issued at 307 AM MDT Sat Jul 16 2016
Latest upper air analysis shows northwest flow over the plains with
an upper level ridge axis to the west. Multiple small scale short
wave troughs were in the flow around the ridge to the west.
Today through Monday the weather pattern will continue to be active
as numerous upper level short wave troughs move across the Tri-State
Area bringing chances for rain with them.
This morning there may be some lingering thunderstorms east of
Highway 83 ahead of an upper level short wave trough. These storms
will be east of the area by mid morning if they do develop. Any
patchy fog that developed around sunrise will be gone by mid morning
too.
During the afternoon the cold front that moved through the area
yesterday will move back north as a warm front. Meanwhile an upper
level short wave trough will move across the northern part of the
Tri-State Area north of the warm front. With lower CINH ahead of
the warm front and lower dew point depressions at the LCL, am
expecting isolated to scattered storms to develop north of Highway
36. Most of the storm activity will be north of the area. Behind
the front the warmer air mass will allow the breezy low level jet to
mix to the ground, producing winds similar to yesterday or a bit
stronger.
During the afternoon the surface low in East Central Colorado will
push the dry line to the KS/CO border. However the dry line will be
behind the warm front in the drier more stable air so am not
expecting any storm development along the dry line as a result.
Strong to severe storms are expected north of the warm front this
afternoon into the early evening. Large hail up to baseball size
will be possible with the strongest storms. Damaging winds will
also be possible. There may be a threat for tornadoes north of the
warm front. However am not sure if the 0-1km shear will be strong
enough to support tornadic development north of the front.
This evening the upper level short wave trough will continue to move
across the northern part of the area. Meanwhile the front will
continue northward and briefly stall over the northern border of the
area during the overnight hours. By this time the short wave trough
and associated storm activity will be east of the area. Before
sunrise the front will be pushed back south as a cold front.
Sunday morning the cold front will stall along the southeast and the
western border. During the day the upper level flow will be
laminar. Toward evening an upper level short wave trough will move
over East Central Colorado from the west. Am expecting storms to
fire off the dry line along the western border of the Tri-State
Area. The storms should remain over East Central Colorado since the
lift from the upper level short wave trough will not extend very far
across the CO state line if at all.
During the evening the short wave trough will progress across the
Tri-State Area. Soundings show the majority of the low dew point
depressions to be above 600mb, so am not expecting there to be very
much storm coverage as the short wave trough moves across the area.
Monday the warm front will move back north to roughly Highway 24.
Behind the front drier, warmer air will move into the southern half
of the Tri-State Area. A few upper level short wave troughs will
move across the area during the day. However most of the low dew
point depressions will be in the mid and upper levels of the
environment. If any precipitation does occur am thinking it will be
from elevated showers associated with the passage of these short
wave troughs. There may be enough CAPE for a thunderstorm or two to
develop.
Monday evening a stronger upper level short wave trough will move
across the Tri-State Area. The front will move north of the Tri-
State Area by midnight. Meanwhile mid and upper level dew points
will increase as well leading to a better chance for storms to
develop with the trough passage. Storms may train along the front as
the front moves northward. This may lead to training thunderstorms
along the front. The storm activity will end from west to east
across the Tri-State Area during the overnight hours as the short
wave trough exits the area.
.LONG TERM...(Tuesday through Friday)
Issued at 307 AM MDT Sat Jul 16 2016
Tuesday through Friday shows strong ridging over the central CONUS.
For the most part the GFS and European agree on upper and mid level
patterns in the beginning of the period. Each day has potential
precipitation chances via the GFS, the European is a little drier at
times. Due to the slight differences between the two models slight
PoPs were included the days where a stronger signal was prevalent in
either model. The days precipitation chances are possible (primarily
Thursday and Friday) the moisture will move up into the CWA from
Arizona and the Gulf of California. As the end of the long term
period approaches the models start to differ slightly in upper level
pattern. The GFS has ridging over the western portion of the CONUS
and weak troughing in the east; that pattern is the primary driving
factor for precipitation chances. The European on the other hand has
the ridge more east (more over the central CONUS) and amplified than
the GFS; which explains the drier signal. Overall, this pattern will
limit moisture and PoP chances until the ridge weakens or moves
east. Do to the strength of the ridge, temperatures will be in the
upper 90s to low 100s in the beginning of the period. The latter
half of the period could see slightly cooler temperatures if the GFS
holds true, which is what is currently forecasted.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1140 AM MDT Sat Jul 16 2016
VFR at KGLD through the period. Thunderstorm development this
afternoon is expected to remain well northwest and north of the
terminal. Low level wind shear will develop after 02Z as a strong
low level jet develops around sunset.
At KMCK, VFR this afternoon into early evening. Thunderstorms are
forecast to develop over northeast Colorado late this afternoon
and eventually track across southern Nebraska approaching the
terminal in the 02-06Z time frame with gusty winds and MVFR
ceilings.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...DLF
SHORT TERM...JTL
LONG TERM...CLT
AVIATION...DLF
Area Forecast Discussion
National Weather Service Dodge City KS
1226 PM CDT SAT JUL 16 2016
...Updated Short Term...
.SHORT TERM...(This evening through Sunday)
Issued at 1226 PM CDT Sat Jul 16 2016
Much quieter weather pattern unfolding for SW Kansas. A virtually
clear sky early this afternoon. S/SE winds will become strong and
gusty this afternoon, in response to a 994 mb surface low near
Limon, Colorado and about a 10 mb surface pressure gradient
between Syracuse and Kiowa. Some gusts of 30-35 mph will be noted.
12z NAM and HRRR model runs, which did an excellent job
forecasting last night`s thunderstorms, both keep tonight`s
expected MCS activity mainly north of SW Kansas, across NW Kansas
into Nebraska. Kept a slight chance of convection for northern
Ellis county through tonight, as that zone will be closest to the
Nebraska convection, but am not expecting much. A strong
pronounced low level jet is progged by all models to develop after
sunset, with 850 mb winds as high as 60 kts. As such, south winds
will remain quite elevated all night. This, in turn, will keep
temperatures quite elevated, with most locales only falling to the
lower 70s Sunday morning.
Sunday...Mostly sunny and hot. Strong upper high begins to build
strongly into the plains, with 500 mb heights rising sharply from
590 dm Saturday, to 594 dm Sunday afternoon. Afternoon
temperatures will be hotter in response, but not as hot as some
guidance indicates. Lack of downslope, the upper high organizing
east of SW KS near the Ozarks, and most importantly, lush
vegetation and standing water from recent rainfall...will all slow
down the heating trend. GFS/MAV/MEX guidance in the 100s is too
hot for Sunday. Forecasted upper 90s for most zones, and wouldn`t
be surprised if I am still several degrees too warm. NAM/ECMWF
both suggest perhaps an isolated thunderstorm across the far W/NW
zones late Sunday afternoon, but with weak shear and warming
temperatures aloft, am not expecting much.
.LONG TERM...(Sunday through Friday)
Issued at 243 AM CDT Sat Jul 16 2016
For Sunday, a shortwave trough moves across the Northern Plains
pushing a frontal system into western Kansas. Winds are warm and
southerly near Dodge and south and more easterly north of the front.
Highs will be around 100 near Dodge City and south and slightly
cooler north in the mid to upper 90s. Models show little to no
chances for storms with the front at this time.
After Sunday, upper level ridging and warming build deeply into the
Plains with dry conditions and highs in the upper 90s to around 100
each day.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1226 PM CDT Sat Jul 16 2016
Airports expected to remain free of thunderstorms through this
evening. Perhaps an isolated -TSRA west of GCK this afternoon, and
TSRA appear likely north of HYS tonight, but kept any mention of
convection out of the 18z TAFs. Strong S/SE winds will impact
aviation operations this afternoon, gusting over 30 kts at times,
in response to 994 mb surface low near Limon Colorado. A strong
pronounced low level jet is forecasted tonight, with NAM
forecasting 850 mb winds near 60 kts. Expect southerly winds to
remain elevated overnight, along with widespread low level wind
shear.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 94 74 99 70 / 10 10 10 10
GCK 95 71 97 69 / 10 10 10 10
EHA 97 71 100 70 / 10 10 10 10
LBL 98 72 101 70 / 10 0 10 10
HYS 90 72 97 71 / 10 20 10 20
P28 94 75 100 73 / 10 10 0 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Turner
LONG TERM...Kruse
AVIATION...Turner
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
632 AM CDT SAT JUL 16 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 301 AM CDT SAT JUL 16 2016
Isentropic lift on the 310-320 K surfaces should begin to increase
in the next few hours over central KS. Expect that scattered showers
and storms will develop over central KS and move to the east
northeast through the late morning hours. The NAM is the aggressive
with keeping the lift across the forecast area through the early
afternoon. Consensus is that the instability this morning will be
around 1000-2000 j/kg and given the convection will be elevated the
shear will be limited. Therefore expect that these storms will stay
below severe limits. All of this is in to response of a weak front
stretched across central KS. A surface low pressure will deepen over
northeast CO later today, which will lift the front into southwest
NE. Soundings show that an elevated mix layer builds over the area
this afternoon, which should prevent any surface based convection.
Current water vapor shows an on going MCS in southeast MT supported
by a mid level shortwave. This wave will track over the northern
plains later today, and should initiate convection in SD, while
additional development is possible near the surface low pressure in
western NE. These clusters of storms could develop into several MCSs
that will move east southeastward during the evening hours. The low
level jet is forecasted to increase during this time frame, and may
support an MCS to move into portions of northeast KS, and or may
initiate additional convection over any existing cold pools across
eastern NE. There will be plenty of instability across the forecast
area, and sufficient shear needed to sustain a balanced cold pool
with the environment. As of now the most most likely track for an
MCS will be eastern NE and western IA. Any MCS will pose a risk for
damaging wind especially for areas along and north of I-70 through
the overnight.
.LONG TERM...(Sunday through Friday)
Issued at 301 AM CDT SAT JUL 16 2016
Frontal boundary sagging southward out of the northern plains into
western Kansas by late Sunday afternoon slows to a near stop through
the overnight hours into early Monday. Stronger flow to the north
and overnight LLJ also focus better chances north of the area late
Sunday night into early Monday. Initial impacts on temperatures
will be for a warm boost on Sunday as the mid level thermal ridge
ahead of the front rises into northeast Kansas, and have highs
from the lower 90s far northeast to near 102 out in central
Kansas, with overnight lows holding generally in the low 70s west
to middle 70s east. Could get a break with some cool outflow from
storms to the northeast. Have only kept low PoPs for early Sunday
and again in the overnight hours as think most storms will stay
north and east. Surface high advances farther south and east into
Monday, as upper flow takes a shift to the west northwest. This
could give one last day in the low to middle 90s before
temperatures ramp up for the week. Some models generating very
light QPF for Monday, but outside the boundary to focus on, not
seeing a strong source of lift and have just kept a slight chance
near or north of the front on Monday.
Northeasterly return of the 850mb front brings warm advection over
eastern Kansas Monday night, and have slight to chance for precip
mainly north of I70, pivoting over the eastern counties through
Tuesday afternoon. Temperatures rise out west back to upper 90s,
spreading into the eastern counties by Wednesday afternoon. Many
locations expected to see the century mark for Thursday and Friday
as the center of the upper high shifts over southern Kansas.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 626 AM CDT SAT JUL 16 2016
VFR conditions expected most of the taf period. There is a slight
chance for isolated showers and storms through the morning and
early afternoon. Due to low confidence and isolated coverage did
not include in the taf. Low level wind shear is likely tonight
across all of the taf sites.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Sanders
Area Forecast Discussion
National Weather Service Wichita KS
629 AM CDT SAT JUL 16 2016
.SHORT TERM...(Today through Sunday night)
Issued at 325 AM CDT Sat Jul 16 2016
A large convective complex continues to push across SW OK at this
time, with most of the low level moisture transport feeding this
complex. Latest RAP does show some weak moisture transport across
nrn OK trying to push into South Central KS by around sunrise. This
could lead to a few hit-or-miss showers/storms for areas over South
Central KS early this morning, with this chance slowly shifting
slowly to the east over the Flint Hills as the morning progresses.
Most of the areas west of I-135 will be characterized by warming mid
level temps, which will effectively cap off any convective chances
for the afternoon/evening hours. Expect this to be the last "cool"
day with seasonal max temps around 90.
The warm advection will continue across the plains into the evening/
overnight hours, with most of the 850-700h moisture transport
expected to push north of the area into Neb. Think some severe
convection will develop along the dryline expected to located over
W/SW Neb and expect this convection will evolve into an eastward
moving complex of storms (MCS) late this evening/overnight, as
moisture transport increases and veers to the NE, keeping most of
the convection well to the north-northeast of the forecast area.
The warm advection looks to continue for Sunday, with warm 850h
temps, with critical 1000-850h thickness values suggesting max temps
rising into the upper 90s for most areas and to near 100 in Central
KS. Expect most locations to remain dry on Sunday as a warm elevated
mixed layer spreads over the area. The only concern will be whether
tonight`s late night MCS can throw out an outflow boundary that may
be located across Central KS (along I-70) for Sun afternoon/evening.
Latest model runs suggest some sort of boundary will be located
across portions of north Central KS, either from an outflow or a
weak surface trough as the mid level ridge builds across the area.
As the temps rise Sun afternoon, could see areas along the boundary
reach their convective temp, but most locations will remain capped.
So could see a diurnally driven isolated storm or two develop along
this boundary for Sunday afternoon/evening.
Ketcham
.LONG TERM...(Monday through Friday)
Issued at 325 AM CDT Sat Jul 16 2016
Expect the subtropical ridge to continue to build across
the plains for the beginning of the week. The warming mid level
temps will lead to a strong cap building across the area with dry
conditions with surface temps climbing into the upper 90s for Mon
through Thu, with the warmest days expected to be Thu/Fri. Will also
see humid conditions across the area too, which may lead to heat
advisories being posted across the region for the middle of the work
week. The higher surface dewpoint air will probably keep max temps
in the upper 90s as heating goes to burning off the higher dewpoint
air, but expect heat index values of 100-105 by the Mon-Thu.
Ketcham
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 614 AM CDT Sat Jul 16 2016
a few areas of patchy IFR and MVFR ceilings impacted terminals
across central Kansas early this morning. These ceilings are
expected to mix out later this morning and should be quite short
lived. For now only included brief mentions of these low ceilings
at KGBD, where GOES Fog and Low Stratus products show the best
coverage. Later this morning, expect winds to come around to the
south-southeast at all terminals. As we progress through the
morning hours winds will become gusty, especially at terminals in
central and south central Kansas, as the pressure gradient
strengthens across the region and deep mixing develops. Tonight as
the pressure gradient holds strong and the low-level jet develops
across the region, expect the gusty winds to linger through the
overnight hours.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 91 74 98 75 / 20 10 0 0
Hutchinson 90 73 98 74 / 20 10 10 10
Newton 90 73 97 73 / 20 10 0 10
ElDorado 90 73 96 74 / 20 10 0 0
Winfield-KWLD 91 74 96 75 / 20 10 0 0
Russell 92 73 100 72 / 10 10 10 20
Great Bend 92 73 101 73 / 10 10 10 20
Salina 92 74 101 74 / 20 10 10 20
McPherson 90 73 97 73 / 20 10 10 10
Coffeyville 90 74 94 75 / 20 10 0 0
Chanute 90 73 94 74 / 20 10 0 10
Iola 89 73 94 74 / 20 10 10 10
Parsons-KPPF 89 73 93 74 / 20 10 0 0
&&
.ICT Watches/Warnings/Advisories...
None.
&&
$$
SHORT TERM...Ketcham
LONG TERM...Ketcham
AVIATION...JMR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
303 AM CDT SAT JUL 16 2016
.SHORT TERM...(Today and Tonight)
Issued at 301 AM CDT SAT JUL 16 2016
Isentropic lift on the 310-320 K surfaces should begin to increase
in the next few hours over central KS. Expect that scattered showers
and storms will develop over central KS and move to the east
northeast through the late morning hours. The NAM is the aggressive
with keeping the lift across the forecast area through the early
afternoon. Consensus is that the instability this morning will be
around 1000-2000 j/kg and given the convection will be elevated the
shear will be limited. Therefore expect that these storms will stay
below severe limits. All of this is in to response of a weak front
stretched across central KS. A surface low pressure will deepen over
northeast CO later today, which will lift the front into southwest
NE. Soundings show that an elevated mix layer builds over the area
this afternoon, which should prevent any surface based convection.
Current water vapor shows an on going MCS in southeast MT supported
by a mid level shortwave. This wave will track over the northern
plains later today, and should initiate convection in SD, while
additional development is possible near the surface low pressure in
western NE. These clusters of storms could develop into several MCSs
that will move east southeastward during the evening hours. The low
level jet is forecasted to increase during this time frame, and may
support an MCS to move into portions of northeast KS, and or may
initiate additional convection over any existing cold pools across
eastern NE. There will be plenty of instability across the forecast
area, and sufficient shear needed to sustain a balanced cold pool
with the environment. As of now the most most likely track for an
MCS will be eastern NE and western IA. Any MCS will pose a risk for
damaging wind especially for areas along and north of I-70 through
the overnight.
.LONG TERM...(Sunday through Friday)
Issued at 301 AM CDT SAT JUL 16 2016
Frontal boundary sagging southward out of the northern plains into
western Kansas by late Sunday afternoon slows to a near stop through
the overnight hours into early Monday. Stronger flow to the north
and overnight LLJ also focus better chances north of the area late
Sunday night into early Monday. Initial impacts on temperatures
will be for a warm boost on Sunday as the mid level thermal ridge
ahead of the front rises into northeast Kansas, and have highs
from the lower 90s far northeast to near 102 out in central
Kansas, with overnight lows holding generally in the low 70s west
to middle 70s east. Could get a break with some cool outflow from
storms to the northeast. Have only kept low PoPs for early Sunday
and again in the overnight hours as think most storms will stay
north and east. Surface high advances farther south and east into
Monday, as upper flow takes a shift to the west northwest. This
could give one last day in the low to middle 90s before
temperatures ramp up for the week. Some models generating very
light QPF for Monday, but outside the boundary to focus on, not
seeing a strong source of lift and have just kept a slight chance
near or north of the front on Monday.
Northeasterly return of the 850mb front brings warm advection over
eastern Kansas Monday night, and have slight to chance for precip
mainly north of I70, pivoting over the eastern counties through
Tuesday afternoon. Temperatures rise out west back to upper 90s,
spreading into the eastern counties by Wednesday afternoon. Many
locations expected to see the century mark for Thursday and Friday
as the center of the upper high shifts over southern Kansas.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1153 PM CDT FRI JUL 15 2016
VFR conditions are likely through the TAF period although some
scattered clouds around 2500 feet are expected to move over TAF
sites between 08Z-13Z. There is a small chance for these to have
greater coverage, and also to be associated with scattered
thunderstorms, so for now have indicated SCT025 and VCTS during
the most likely timing at each site. Small chances for storms
through the day Saturday, but no period with high enough chance to
highlight in TAF.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Barjenbruch
Area Forecast Discussion
National Weather Service Dodge City KS
245 AM CDT SAT JUL 16 2016
...Updated for Long Term...
.SHORT TERM...(Today and tonight)
Issued at 233 AM CDT Sat Jul 16 2016
For today, upper level ridging and warming move back into the
Central Plains. Light southeast winds becoming southerly and
increase to 20 to 35 mph in the afternoon as a warm front moves back
across western Kansas. There could be some isolated thunderstorms
near the Colorado border and near Medicine Lodge by later afternoon
and evening. The best instability is in parts of south central
Kansas with forecast CAPE around 3000 J/kg. If a storm does go it
could become marginally severe. High today will be much warmer with
the warmer southerly winds with highs in the upper 90s far west to
the lower to mid 90s elsewhere with mostly clear skies.
For tonight, expect mostly clear skies and mild lows in the lower to
middle 70s and south to southwest winds of 10 to 15 mph.
.LONG TERM...(Sunday through Friday)
Issued at 243 AM CDT Sat Jul 16 2016
For Sunday, a shortwave trough moves across the Northern Plains
pushing a frontal system into western Kansas. Winds are warm and
southerly near Dodge and south and more easterly north of the front.
Highs will be around 100 near Dodge City and south and slightly
cooler north in the mid to upper 90s. Models show little to no
chances for storms with the front at this time.
After Sunday, upper level ridging and warming build deeply into the
Plains with dry conditions and highs in the upper 90s to around 100
each day.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1203 AM CDT Sat Jul 16 2016
VFR conditions are expected post MCS with light upslope winds. As
a pressure gradient increases, winds will shift to the south and
increase to 18-28kt late this morning and into the afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 94 73 99 70 / 10 10 10 10
GCK 95 71 97 69 / 10 10 10 10
EHA 97 70 100 70 / 10 10 10 10
LBL 98 72 101 70 / 10 10 10 10
HYS 90 72 100 71 / 10 10 10 20
P28 94 74 100 73 / 10 10 10 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Kruse
LONG TERM...Kruse
AVIATION...Kruse
Area Forecast Discussion
National Weather Service Dodge City KS
245 AM CDT SAT JUL 16 2016
...Updated for Long Term...
.SHORT TERM...(Today and tonight)
Issued at 233 AM CDT Sat Jul 16 2016
For today, upper level ridging and warming move back into the
Central Plains. Light southeast winds becoming southerly and
increase to 20 to 35 mph in the afternoon as a warm front moves back
across western Kansas. There could be some isolated thunderstorms
near the Colorado border and near Medicine Lodge by later afternoon
and evening. The best instability is in parts of south central
Kansas with forecast CAPE around 3000 J/kg. If a storm does go it
could become marginally severe. High today will be much warmer with
the warmer southerly winds with highs in the upper 90s far west to
the lower to mid 90s elsewhere with mostly clear skies.
For tonight, expect mostly clear skies and mild lows in the lower to
middle 70s and south to southwest winds of 10 to 15 mph.
.LONG TERM...(Sunday through Friday)
Issued at 243 AM CDT Sat Jul 16 2016
For Sunday, a shortwave trough moves across the Northern Plains
pushing a frontal system into western Kansas. Winds are warm and
southerly near Dodge and south and more easterly north of the front.
Highs will be around 100 near Dodge City and south and slightly
cooler north in the mid to upper 90s. Models show little to no
chances for storms with the front at this time.
After Sunday, upper level ridging and warming build deeply into the
Plains with dry conditions and highs in the upper 90s to around 100
each day.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1203 AM CDT Sat Jul 16 2016
VFR conditions are expected post MCS with light upslope winds. As
a pressure gradient increases, winds will shift to the south and
increase to 18-28kt late this morning and into the afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 94 73 99 70 / 10 10 10 10
GCK 95 71 97 69 / 10 10 10 10
EHA 97 70 100 70 / 10 10 10 10
LBL 98 72 101 70 / 10 10 10 10
HYS 90 72 100 71 / 10 10 10 20
P28 94 74 100 73 / 10 10 10 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Kruse
LONG TERM...Kruse
AVIATION...Kruse
Area Forecast Discussion
National Weather Service Dodge City KS
234 AM CDT SAT JUL 16 2016
...Updated for Short Term...
.SHORT TERM...(Today and tonight)
Issued at 233 AM CDT Sat Jul 16 2016
For today, upper level ridging and warming move back into the
Central Plains. Light southeast winds becoming southerly and
increase to 20 to 35 mph in the afternoon as a warm front moves back
across western Kansas. There could be some isolated thunderstorms
near the Colorado border and near Medicine Lodge by later afternoon
and evening. The best instability is in parts of south central
Kansas with forecast CAPE around 3000 J/kg. If a storm does go it
could become marginally severe. High today will be much warmer with
the warmer southerly winds with highs in the upper 90s far west to
the lower to mid 90s elsewhere with mostly clear skies.
For tonight, expect mostly clear skies and mild lows in the lower to
middle 70s and south to southwest winds of 10 to 15 mph.
.LONG TERM...(Saturday night through Friday)
Issued at 216 PM CDT Fri Jul 15 2016
Not much emphasis on the Long Term given quieter weather regime
through much of this period and all the focus on the more
important near term severe weather threat. Looking at the long
term global models, they all still agree on a 600 decameter 500mb
high settling in through much of the week which will result in
persistent daytime highs around 100 each day and lows generally in
the lower 70s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1203 AM CDT Sat Jul 16 2016
VFR conditions are expected post MCS with light upslope winds. As
a pressure gradient increases, winds will shift to the south and
increase to 18-28kt late this morning and into the afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 94 73 99 70 / 10 10 10 10
GCK 95 71 97 69 / 10 10 10 10
EHA 97 70 100 70 / 10 10 10 10
LBL 98 72 101 70 / 10 10 10 10
HYS 90 72 100 71 / 10 10 10 20
P28 94 74 100 73 / 10 10 10 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Kruse
LONG TERM...Umscheid
AVIATION...Kruse
Area Forecast Discussion
National Weather Service Goodland KS
1152 PM MDT FRI JUL 15 2016
.UPDATE...
Issued at 906 PM MDT Fri Jul 15 2016
Just completed an update. First was to add pops this evening to
the northeast corner. Weak surface convergence along with a weak
shortwave trough have caused thunderstorms to develop in that
area. Next the newer guidance is supporting a little further west
solution of pops during the overnight hours so moved those slight
chance pops further west.
Lastly, high resolution coming in with more fog, especially in the
western half. So increased to areas in the area with patchy fog
everywhere. Also increased sky cover as well.
UPDATE Issued at 543 PM MDT Fri Jul 15 2016
Earlier in the hour completed an update. Gust/cold front have
pushed through the area and have pushed thunderstorms and severe
threat to the south of the area. Mesoscale influences have caused
the front to be further south than most hires/Cams have taken into
account. Overall the HRRR is catching the current situation well
and better than other output in all facets and relied upon it for
this update. Much more stable air mass is now over our area. As a
result have cancelled the severe thunderstorm watch and lowered
pops through the evening.
Does not look to be a lot of lift around this evening except for
upslope/terrain influences. This has caused some thunderstorms to
develop to our west. Not sure how far east they will make it. Have
kept low chance and slight chance pops in the southern and western
areas through the middle of the night.
Mid level warm air advection and shortwave trough push across/closer
to the area after midnight. As a result left the slight chance
pops in over the northeast after midnight. Am a little concerned
now with the front to our south...more overrunning and lift will
occur. Will let newer data come in and assess the need to expand
pops.
Also due to the strong cold/gust front moving through and outflow
from strong outflow from storms to our south...strong upslope
winds are in place over the entire area. Some higher stratus has
already developed and think that will remain and expand through
the night. Increased cloud cover but may need to increase it more.
Also hires output is starting to indicate fog development. That is
reasonable given current conditions and inserted patchy fog
through early tomorrow morning.
&&
.SHORT TERM...(This afternoon through Tonight)
Issued at 147 PM MDT Fri Jul 15 2016
Thunderstorms have already developed in vicinity of meso low near
the Colorado and Kansas border. SB CAPE exceeds 3000 J/KG with
axis extending along and ahead of stalled front (currently near
Goodland)in northeast to southeast orientation. Strong mid level
flow along with veering wind profiles have resulted in effective
helicity values exceeding 300 m2/s2 overlapping this strong region
of CAPE. LCLs are a little high in favorable warm sector, however
tornadic threat exists considering high CAPE/shear environment.
Large hail (baseball size or larger) and strong microbursts will
be threats with the activity this afternoon.
High resolution guidance shows this activity increasing in
coverage and eventually merging into a MCS as shortwave (nose of
which is in central Colorado) moves over this stalled front. This
is then shown to dive south along CAPE axis, which puts the peak
threat for severe weather no through around 00z in our CWA.
Increasing ascent and the possibility that the front begins to
lift back north raises the possibility that additional activity
(likely elevated) could develop across much of our CWA this
afternoon/evening. Some guidance has shown possibility for
elevated convective activity developing later in the evening and
overnight behind the departing MCS, so I lingered slight chances
in our north and east where this weaker signal is shown.
A similar air mass as this morning is indicated overnight and
depending on clearing we should have similar low temps (60-66).
.LONG TERM...(Saturday through Friday)
Issued at 143 PM MDT Fri Jul 15 2016
Saturday and Sunday: Isolated to scattered thunderstorms mainly
across far southwest Nebraska will be possible Saturday afternoon
with isolated thunderstorm chances elsewhere as a weak shortwave
traverses the region. A ridge will begin to slowly build into the
central Plains through the day on Sunday with an axis centered in
northern TX and southern OK. Moisture levels will increase in the
western portions of the CWA along the edge of the ridge which could
lead to slight chances for afternoon/evening thunderstorms on
Sunday and Monday. There will be modest mid-afternoon
instability on Sunday and good instability on Monday.
Tuesday through Thursday: High pressure ridge at the H5 lvl will
approach 600dam by early Tuesday, remaining locked in over the
region through the forecast period. Afternoon high temperatures
will reach or slightly exceed 100 degrees across much of the CWA
with dew points in the 50 to 55 degree range on Wednesday and
Thursday. PoPs are nearly nil Tuesday through Thursday as the
ridge will prevail and dry, hot, weather will dominate the central
High Plains.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1144 PM MDT Fri Jul 15 2016
Continued complicated set of tafs. For Kgld...conditions will
start at mvfr and then become ifr from 12z to 15z. Conditions will
then improve at 15z with mvfr becoming vfr around 18z. During the
morning southerly winds will increase to near 20 knots with gusts
around 30 knots. Near sunset the winds will decrease to 13 knots
gusts to near 19 knots. Thunderstorms for the rest of the night
and tomorrow evening are expected to not affect the site.
For Kmck...by 09z conditions will change from vfr to mvfr. After
that conditions will quickly lower ifr/lifr. Mvfr conditions will
return around 15z and become vfr once again around 18z.
Thunderstorms for the rest of tonight are now expected to not
affect the site. Around 18z southerly winds will increase to
around 16 knots with gusts to around 24 knots. These will decrease
around 02z. It is at that time that a thunderstorm complex should
start affecting the site. Since this is in the last 6 hours of the
forecast, chose to handle with a vcts at this time.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...DR
LONG TERM...TL
AVIATION...BULLER
Area Forecast Discussion
National Weather Service Tucson AZ
930 PM MST SUN JUL 17 2016
.SYNOPSIS...Adequate moisture will provide scattered mainly afternoon
and evening showers and thunderstorms through Wednesday. A slight
decrease in daily coverage of showers and thunderstorms should then
occur Thursday into next weekend.
&&
.DISCUSSION...Showers and thunderstorms continued to increase in
coverage late this evening, with a few making their way through the
greater Tucson area. Recent HRRR solutions suggested that this
activity will gradually diminish after midnight tonight, with debris
cloudiness lingering over the area for tomorrow morning. Current
forecast appeared to be handling the trends well, so no updates
anticipated at this time. Please refer to the additional sections in
this product for more details.
&&
.AVIATION...VALID THRU 19/06Z.
Isolated to scattered SHRA/TSRA will occur through the period. Brief
wind gusts of 35-40 kts and MVFR conditions may occur with the
stronger TSRA. Outside of thunderstorm outflows, sfc wind will
generally be wly/nwly at 8-12 kts, weakening to less than 10 kts and
becoming variable in direction overnight into Monday morning. Sfc
wind Monday will be wly/nwly at 8-12 kts. Aviation discussion not
updated for TAF amendments.
&&
.FIRE WEATHER...Plenty of moisture will remain in place this week
for daily chances of mainly afternoon and evening showers and
thunderstorms. A slight decrease in rain chances may occur late in
the week into next weekend. Outside of gusty thunderstorm/outflow
winds, expect typical diurnal 20-ft wind patterns each day. Stronger
gusts are possible through the Gila River Valley when winds are
northwesterly in direction.
&&
.PREV DISCUSSION...The various mesoscale models suggest at the very
least that convective debris clouds should encompass much of the
area later tonight, then clearing skies may occur earlier Monday
versus today. Given this scenario, have opted for scattered
showers/tstms Monday afternoon/ evening mainly from Tucson
eastward/southward.
Expect similar coverage of showers/tstms to occur Tuesday afternoon/
evening. The potential for somewhat stronger thunderstorms may exist
Tuesday, as the progged flow may be more favorable for storm motions
from the Mogollon Rim area. Fairly deep moisture will remain over
the area Wednesday as strong high pressure aloft is progged to be
over southern Missouri/northern Arkansas. Thereafter, a gradual
drying trend continues to be depicted via the GFS/ECMWF during the
Thursday-Sunday period. Moisture should remain sufficient for
isolated to scattered mainly afternoon and evening showers and
thunderstorms Thursday through next Sunday.
High temps Mon-Tue will be quite close to seasonal normals, then a
return of above normal temps is forecast to occur starting Wednesday
and especially Thur-Sun.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
926 PM PDT SUN JUL 17 2016
.SYNOPSIS...
Seasonable temperatures will continue into early this week with a
trough of low pressure in place. High pressure over the central
U.S. will then build and expand westward. A warming trend is
forecast through the end of the week, with well above normal
temperatures possible for inland areas through the weekend.
&&
.UPDATE...
Southwest flow aloft remains over the area between a trough of low
pressure off the Pacific Northwest Coast and a ridge of high
pressure over the Southeast United States. At the surface, onshore
flow remains in place across the area keeping persistent marine
layer stratus hugging the California Coast.
Onshore flow should continue to be the key staple of the weather
pattern for early this week as southwest flow aloft remains in
place. Southwest flow aloft will start to weaken throughout the
week as the ridge to the east start to nudge west into the Desert
Southwest.
&&
.PREV DISCUSSION...
SHORT TERM...By Tuesday a strong 598 dm high sets up over the
Southern Plains and expands both east and westward taking up most
of the southern CONUS. Heights, and boundary layer temps will be
on the rise Tuesday in response to the building upper lvl ridge
over the region. Expect high temps to jump up 2-6 degrees with
most valleys expecting highs in the upper 80s to mid 90s. The
Antelope Valley will reach the upper 90s to around 101 degrees.
Low clouds should not spread as far inland due to the upper ridge
helping to squash down the inversion. LA/VTU county valleys should
be mostly clear into Wed morning, or maybe skirting the San
Gabriel Valley. The warming trend will continue into Wednesday as
the strong upper ridge translates to the west. This will cause the
upper ridge to strengthen even further. Onshore gradients will
also trend weaker helping to further warm most areas Wednesday. An
additional 3 to 5 degrees of warming is expected across the entire
forecast area. Highs are expected to reach the mid 90s to around
101 degrees in valley locations, while the Antelope Valley will
experience widespread triple digit heat up to 104 degrees. Once
again low clouds will be limited to coastal areas. some patchy
dense fog could be a possibilty Wed night.
LONG TERM...Both the GFS and EC models remain in agreement by
keeping the strong upper ridge across the entire southern half of
the CONUS including the bottom half of California. High temps on
Thursday will be fairly similar to Wednesday, additional warming
is expected Fri and Saturday with warmest valley locations
expected to reach around 102 degrees with most valleys remaining
in the mid to upper 90s. The Antelope Valley will continue to to
be hot with max high temps reaching 106 degrees. Coastal areas
will also see some limited warming. Beaches will remain in the
lower to mid 70s while inland coastal areas will reach the upper
80s each day. There will be a slight decrease in temps on Sunday,
but high temps away from the coast will continue to remain above
avg for this time of year.
There will be some monsoonal moisture to the east of the area
later this week. But at this time, convective parameters continue
to look anemic over the high deserts and adjacent mountains. 850
mb dewpoints remain rather dry through the next 7 days as well. If
some storm complex systems develop over Mexico or Arizona, and the
upper ridge shifts slightly, this could change the pattern. So
will continue to monitor the forecasts for the potential for
thunderstorms in our local mountains later in the week and next
weekend. But for now, it is not look promising for any convection
to occur.
&&
.AVIATION...18/0000Z.
The marine layer was around 1100 feet deep at KLAX. The top of the
inversion was around 2350 feet with a temperature of 25 degrees
Celsius.
North of Point Conception...IFR conditions should spread in
through 05Z, then lower to the LIFR category through 10Z.
Conditions should improve between 14Z and 16Z with VFR conditions
developing between 16Z and 18Z. There is a chance of LIFR
conditions at KPRB between 10Z and 16Z.
South of Point Conception...Predominantly MVFR conditions will
spread into coastal terminals through 08Z, then likely into the
valley terminals through 13Z at the latest. There is a chance of
IFR conditions north of KOXR. Conditions should improve to VFR
between 16Z and 20Z. Coastal terminals could struggle to clear on
Monday afternoon.
KLAX...MVFR conditions will spread around 0330Z, or 08Z at the
latest. Conditions should improve to VFR between 17Z and 19Z.
KBUR...VFR conditions should continue through at least 10Z, then
there is a 70 percent chance of MVFR conditions through 16Z. The
most likely time of arrival will fall in between 1130Z and 1330Z.
&&
.MARINE...17/900 PM.
A Small Craft Advisory for the Outer Waters northwest of the
Channel Islands has been extended until early Tuesday morning.
There is a 50 percent chance that this advisory may need to be
extended into early Wednesday morning and/or expanded into the
entire Outer Waters and to the nearshore waters north of Point
Sal.
Swells from TC Darby are mixed with southern hemisphere swell
from 190 degrees and will persist today. TC Estelle was
approximately 365 nm south-southwest of the southern tip of Baja.
The forecast track is similar to TC Darby and swells from Estelle
will begin to arrive Tuesday from 170-180 degrees which will
generate extra current and surging along exposed south facing
shores.
&&
.FIRE WEATHER...17/130 PM.
Most mountains and interior valleys will experience daily minimum
humidities under 10 percent with poor overnight recoveries through
early Tuesday. The winds will be fairly typical for this time of
the year...except for enhanced southwest flow with gusts between
30 and 50 mph over the San Gabriel Range, Antelope Valley, and
interior San Luis Obispo Valleys...which will result in isolated
Red Flag conditions each day. With these conditions...and
extremely dry vegetation...elevated fire weather condition exist.
A Red Flag Warning will not be issued however due to a lack of the
duration criteria being met over a large enough area (10 hours for
the Antelope Valley, 6 hours everywhere else). Note...The
neighboring Kern County Mountains and Deserts have different Red
Flag criteria than ours which is why a warning is in place there
while we do not.
From Wednesday to the end of the week, a period of hotter weather
is expected to return to inland areas...but southwest flow will
weaken. While some upper level moisture may move into the region,
the lower levels of the atmosphere are expected to remain very
dry. Elevated fire concerns will exist as a result...especially
over Santa Barbara County where Northwest winds will be on the
rise.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Tuesday For
zones 670-673. (See LAXMWWLOX).
&&
$$
PUBLIC...Hall
FIRE WEATHER...Kittell
AVIATION...Hall
MARINE...Hall
SYNOPSIS...Sukup
weather.gov/losangeles
Area Forecast Discussion
National Weather Service San Francisco Bay Area
849 PM PDT SUN JUL 17 2016
.SYNOPSIS...Cooler than normal temperatures along with overnight
clouds and patchy fog are expected to persist through Tuesday. A
gradual warming trend is then forecast to begin around the middle
of the week.
&&
.DISCUSSION...As of 8:49 PM PDT Sunday...It`s thus far shaping up
to be a cooler/chillier than normal July (average temps as much as
1 to 2 degrees cooler than normal) at many area climate sites, and
the next 2 to 3 days will bring more chilly summer temps. NAEFS
850 mb temps running -1 standard deviation Monday into Wednesday.
Warming trend then revisits Bay Area and Central Coast late this
week and weekend, hot weather probably extending out through the
remainder of July per CPC`s 6-10 day and 8-14 day 500H outlooks as
well as climatology.
An upper level trough off the Pacific Northwest will become carved
a bit deeper tonight into Wednesday prior to weakening late week.
Decent low-mid level cold air advection coupled with a pva center
enters the upper trough tonight and Monday; there are some hints
of cooling showing up at low altitude on the Bodega Bay profiler
very recently. By late week a strong sub-tropical ridge over the
U.S. will retrogress with the western perimeter of the ridge
reaching California late week into early next week. The ECMWF and
GFS are on a similar trend indicating increasing 500H starting
after this Wednesday with heights reaching mid-upper 590 decameters
this weekend and early next week; today`s 12z ECMWF run has trended
stronger since its previous 00z run. Hot and dry especially inland
returns later this week.
&&
.AVIATION...As of 4:58 PM PDT Sunday...Marine layer around 2000
feet deep with 4 mb onshore gradients pushing early cigs over ksfo
this evening ahead of incoming trough. Cigs already over kmry and
soon ksns. Will have to monitor klvk with deep marine layer it
could push past the east bay hills by morning. Only question is
will there be enough cool advection to disrupt the inversion by
morning.
Vicinity of KSFO...bkn 1200 ft already at ksfo so cigs likely in
for the rest of the night. Gusty west winds in excess of 20 kt
with strong gradient in place. Early estimate for clearing Monday
will be around 18z.
SFO Bridge Approach...Cigs to impact approach as early as 02z this
evening...then last through at least 18z Monday.
Monterey Bay Terminals...Low cigs already over kmry and soon ksns
as well as kvwi. Low cigs to stay in place through about 19z
Monday.
&&
.MARINE...as of 3:00 PM PDT Sunday...A low pressure system
developing to the north over the pacific northwest will maintain
moderate northwesterly flow across the northern coastal waters
through late tonight. winds will be locally strong off coastal
points where typical coastal jets form...otherwise light winds
expected over the southern half of the forecast area.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tngt...SCA...Mry Bay until 9 PM
SCA...Pigeon Pt to Pt Pinos 0-10 nm until 9 PM
SCA...Pt Arena to Pt Reyes 0-10 nm until 3 AM
SCA...Pt Reyes to Pigeon Pt 0-10 nm until 3 AM
SCA...Pt Arena to Pigeon Pt 10-60 nm until 3 AM
SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
SCA...SF Bay until 10 PM
&&
$$
PUBLIC FORECAST: Canepa
AVIATION: RWW
MARINE: RWW
Visit us at www.weather.gov/sanfrancisco
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www.Facebook.com/nwsbayarea
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[top]
Area Forecast Discussion
National Weather Service Phoenix AZ
845 PM MST SUN JUL 17 2016
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Although we did finally see a return to more southerly flow aloft,
and a increase in mid-level moisture over south-central AZ,
convective activity has turned out to be virtually nonexistent over
our cwa this so far this afternoon/evening. The primary reason for
the lack of convection is likely due to the fact that a considerable
amount of debris cloudiness from thunderstorms over southeast
AZ/northern Mexico lingered over the region well into Sunday
afternoon, which limited daytime heating, with high only getting
into the upper 90-low 100 range over the lower deserts. The latest
high-res HRRR and RAP13 model runs are now showing more debris
clouds from storms, that are now firing over southeast AZ and along
the international border, moving northward across our cwa later
tonight and Monday morning, perhaps leading to a repeat of what we
saw today, with a cloudy morning once again limiting convective
development in the afternoon/evening. Thus, for the short term, have
reduced pops into the slight chance range for the rest of this
evening across the lower deserts of south-central AZ, and made some
minor adjustments to the hourly temp/wind/dewpoint grids.
&&
.PREVIOUS DISCUSSION...
Tonight...
A fairly complicated pattern with regards to precipitation in south
central AZ will develop later this afternoon and evening. It seems
that mid level disturbances are flying off the shelf so to speak,
and into southern AZ. One feature was noted this morning in weather
balloon data and later with sunlight, visible satellite imagery.
This feature was responsible for increased thunderstorm activity
between Gila Bend and the Mexican border at noon. Then there is
another large mid level circulation feature in northwest Mexico (an
MCV from last nights Sonora Mex convection) that is forecast by the
models to move into AZ just west of Tucson by 5 pm MST. The GFS
model is forecasting a couple of Omega field 500-300 mb bullseye
areas from Pinal County just north to Tucson, to portions of south
Central AZ just north of the Mexican Border this evening.
Therefore with increased moisture, and a couple of nearby dynamical
features, it would be best to increase chances for showers and
thunderstorms over our south central AZ zones, with the best chances
southwest and south of Phoenix. Diminishing showers are expected
after midnight partial clearing skies.
Monday...Much higher monsoon moisture will have spread over the
region by Monday afternoon. With the lack of any notable mid/upper
level disturbances, we will go with a standard low grade monsoon
forecast, i.e. slight chance of afternoon and evening thunderstorms
especially mountains east of Phoenix.
Tuesday...The easterly wave moving out of west Texas this evening
(Sunday) and into Chihuahua and Sonora Mexico is progged by the GFS
model to bodily move into southern Arizona by late Tuesday afternoon
and night. We have elevated the threat of precip slightly in south
central AZ Tuesday evening because of this feature.
Wednesday...Monsoon moisture will be still be entrenched over the
region. Again without any mid/upper level disturbances expected,
only a slight chance of showers and thunderstorms are forecast for
south central AZ.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will flatline at the
114 degree mark. Ouch!
&&
.AVIATION...
The lack of convective activity this evening over south-central AZ
means that the typical shift to easterly winds will likely not take
place until later tonight. We still could also see residual leftover
showers passing through Phoenix later tonight and on Monday morning
as leftover debris clouds from this evening`s crop of thunderstorms
over southeast AZ/NW Mexico once again move across the region,
though shower intensity would most likely be light and impacts
minimal. Some clearing is likely by early Monday afternoon. There is
once again a slight chance for thunderstorms during the late
afternoon/early evening hours on Monday, but confidence is too low
to include in the tafs at this time.
Southeast California/Southwest Arizona including KIPL and KBLH:
Only moderate confidence in terminal forecasts through Monday
morning as thicker 15K-20K cigs spread into SE CA. While
virga/sprinkles may occur briefly, any thunderstorm activity should
remain well east of the area. Sfc winds will favor a southerly
direction (occasionally gusty at KBLH) and southeasterly at KIPL,
though a brief period of evening SW winds at KIPL will be possible
on Monday.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Wednesday through Sunday...
Moisture and relative humidity values will decrease very slightly
through the latter half of the week as high pressure tends to
strengthen and air temperatures climb back to into an above normal
range. Thunderstorm and wetting rain potential will generally be
limited to higher terrain locations north and east of Phoenix, with
better potential for outflow winds heading downhill into lower
elevations of central Arizona. Minimum relative humidity values in a
15 to 25 percent range during the middle of the week will fall to a
10 to 20 percent range by the end of the week. Overnight recovery
will be fair to good. Outside of winds near thunderstorms,
directions will favor an upslope component in the afternoon with
typical gustiness and light overnight drainage.
$$
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...Percha/Vasquez
AVIATION...Percha/MO
FIRE WEATHER...MO
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
330 AM CDT MON JUL 18 2016
.SHORT TERM...(Today and Tonight)
Issued at 313 AM CDT MON JUL 18 2016
An MCS moving through northwest MO has formed an outflow that is
currently pushing southwestward towards far northeast KS. A west to
southwesterly low level jet is intersecting this outflow, and is
responsible for additional storm development in that area. Those
storms may backbuild into far northeast KS in the next few hours
until the cold pool quits progressing or mixes out. There is also
increasing isentropic lift taking place in central KS. Storms have
formed along this axis of lift that stretches back into southwest
KS. The NAM shows this isentropic lift on the 310 K surface nosing
into northeast KS in the next few hours with the coverage most
likely staying isolated to scattered. Therefore have kept slight
chances across the northwest portions of the forecast area through
just after sunrise. How far east these showers and storms extend is
uncertain at this time. Several consecutive runs of the HRRR have
shown this activity reaching east central KS before it weakens as
the low level jet decreases. Given the HRRR is already off on storm
location means perhaps it might not get far into the forecast area
all together. Soundings show about 1500-2000 j/kg of mucape above
drier air in the lower levels and a weak nocturnal inversion. The
effective shear is also around 30 kt, which is marginal from
organization. If a storm were to realize this instability perhaps a
strong localized wind gust could not be ruled out within the
stronger cells.
Later today the temperatures will warm again into the mid 90s to
lower 100s with dew points in the upper 60s to lower 70s. This
combination will cause heat indices between 100-105 this
afternoon, and a heat advisory is in effect.
.LONG TERM...(Tuesday through Sunday)
Issued at 313 AM CDT MON JUL 18 2016
Heat indicies continue their climb through the week, with Tuesday
bringing another day in the 100-105 range, followed by a jump into
the 103-109 range by Wednesday and continuing in that range into
Friday. As a result, and in collaboration with neighbor offices,
have opted to carry a heat advisory through the week. With several
days of heat indicies above 100 by mid week, may need to upgrade
to a warning for the mid to late week time period, considering the
cumulative impacts of several days of heat. In short, outdoor
activities this week will require vigilance about the potential
impacts of several days of heat advisories. Please plan
accordingly.
EC and GFS both try to break down the ridge through the weekend as
an upper trof progresses across the US/Canadian border and sends a
front southward in its wake. EC is stronger and farther southward
with the upper trof, and therefore faster moving the boundary
into southern Kansas by late Saturday. The GFS has a slower
progression but does bring the front through on Sunday. Sensible
weather impacts would be an increasing chance for rain into
Sunday, and a break from the heat of the week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1150 PM CDT SUN JUL 17 2016
VFR conditions are likely through the TAF period. Have winds from
220 degrees in the 34-40 kt range within the 800-1500 foot AGL
layer causing LLWS with light southeasterly winds at the sfc.
Small chance for shra/tsra mainly between 08Z-13Z, but this chance
is very small at TAF sites.
&&
.TOP Watches/Warnings/Advisories...
Heat Advisory from 1 PM this afternoon to 7 PM CDT Friday for
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Barjenbruch
Area Forecast Discussion
National Weather Service Phoenix AZ
750 AM MST MON JUL 18 2016
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Woohoo, the monsoon moisture boundary raced north past Phoenix over
night and this morning was seen pushing up against the higher
elevations of the Mogollon Rim. In other words the southern half of
AZ was in the monsoon moisture soup, and noted by the relatively low
afternoon convective trigger temperatures at a few locations. For
example, based on this mornings weather balloon soundings, the
convective trigger temp at Phoenix is 99 deg F, 97 at Tucson, and 92
deg at Globe/Miami (elevation 3-4 thsd ft msl). Even though the
afternoon thermodynamics are there, the flow aloft has, and will
remain anti-cyclonic and relatively stable today and tonight. In
other words, the situation for today favors low topped afternoon
convection, mostly in the mountains with possible outflows toward
the deserts sparking an isolated desert storm, with convection
dissipating quickly after dark, unless.
Unless like last night, a surge of convective debris clouds from
southeast AZ spread north, creating a well saturated mid level
airmass that a gravity wave sparked a few showers and thunderstorms
in the Phoenix area after midnight. The gravity wave conclusion was
derived from high speed satellite imagery loops.
Beyond today, our office staff eyes are now on the massive inverted
trof seen in water vapor imagery over the north central Mexican
state of Chihuahua. Models the past two days have resolved this
feature very well at the 300/250 mb level, and is forecast to move
into southeast AZ on Tuesday.
For now the low grade monsoon forecast, meaning slight chance of
showers and thunderstorms over the south central AZ deserts and
mountains look ok for now. We will see how the new models handle
Tuesdays inverted trof since model guidance will have incorporated
the Chihuahua weather balloon sounding that is launched once per day
at 12z.
.Previous discussion...503 AM MST...
The weather pattern has finally allowed the typical monsoonal
circulation to return to the area as the combination of troffing
along the Pacific northwest coast and upper ridging over the central
CONUS has allowed southerly to southeasterly flow aloft to set up
across Arizona. This favorable flow has advected considerable
amounts of monsoon moisture into the lower deserts; the latest
Phoenix raob had PWAT up to 1.44 inches and Tucson had 1.5 inches.
Despite the ample moisture, much of it was at mid and upper levels
through, limiting CAPE values. According to the 2 am SPC
mesoanalysis graphic, MLCAPE of consequence (over 500 j/kg) was
still over far SE Arizona with very low amounts in the central
deserts. 2 am radar continued to show showers spreading into south
central Arizona from the southeast and isolated thunderstorms are
possible but any convection that develops should stay on the weak
side into the morning hours. The convection is likely being aided by
weak vort maxes rotating into Arizona around the large scale upper
high. Should significant clouds and showers persist well into the
morning or the early afternoon, instability will again be limited
and storm activity tonight will suffer.
For the next few days, operational models such as the GFS and ECMWF
as well as GEFS data, call for the monsoonal circulation to remain
in place with little change from day to day. Moisture will remain
relatively plentiful, at least from a PWAT perspective as values
upwards of 1.5 inches will stay over much of the lower deserts to
the east of the lower Colorado river valley. Most of the CAPE of
consequence however is advertised to stay pretty much from Maricopa
county eastward each day, suggesting convective potential over the
southwest deserts will be limited, and minimal as you move into the
deserts of southeast California. Steering flow each day will stay
south to southeast but not overly strong, with 700-300mb layer winds
mostly between 10 and 15 knots each day. There will be occasional
vort maxes/weak inverted trofs rotating around the main upper high
and moving north across the central deserts but due to the small
scale of these features, they will not be handled very well by the
models and as such there will be low confidence in any particular
one of these small scale features. As such we will keep a rather low
grade monsoon forecast in place today through Wednesday with slight
chances for mainly afternoon and evening showers and thunderstorms
over the central lower deserts, with better chances over the higher
terrain east of Phoenix. Skies will be partly to mostly cloudy much
of the time, with the greatest amounts of sunshine likely during
later morning through mid afternoon each day. High temperatures will
stay near seasonal normals over south central Arizona today, then
gradually creep up each day with Phoenix approaching 110 by
Wednesday. It will be hotter over the far western deserts and over
SE California as the airmass will be drier there.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will at the
114 degree mark. Ouch! Current forecasts will keep Phoenix at or
above the 110 degree mark each day. At the moment it appears high
temperature will stay below excessive heat warning thresholds but
that could change depending upon just how dry we actually get, and
how high the heights become over the lower deserts.
&&
.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL:
Light showers will remain possible through the early afternoon hours
with light/variable winds and cigs AOA 10k ft. There is an enhanced
risk of gusty southeast winds and blowing dust this evening though
only enough confidence at this point to show a modest wind shift at
most terminals.
Southeast California/Southwest Arizona including KIPL and KBLH:
Scattered/broken high clouds will typical diurnal wind directions and
relatively light. Airmass expected to be too dry to support any
showers or thunderstorms over the next 24-36 hours.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Wednesday through Sunday...
Humidity values will be on the downward trend from Wednesday heading
into the weekend as moisture levels thin and temperatures increase.
Minimum afternoon humidity values will bottom-out in near 10 percent
below 4000` and 20-30 percent above 4000`. Thunderstorm activity,
which is not expected to be significant, will be greatest
Wednesday/Thursday over the mountains then decreasing into the
weekend. Modest at best chances for lower elevation rains. Except for
thunderstorm-driven outflow winds, typical diurnal patterns expected.
$$
.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...Vasquez/CB/Vasquez
AVIATION...Iniguez
FIRE WEATHER...Iniguez
Area Forecast Discussion
National Weather Service Phoenix AZ
503 AM MST MON JUL 18 2016
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
The weather pattern has finally allowed the typical monsoonal
circulation to return to the area as the combination of troffing
along the Pacific northwest coast and upper ridging over the central
CONUS has allowed southerly to southeasterly flow aloft to set up
across Arizona. This favorable flow has advected considerable
amounts of monsoon moisture into the lower deserts; the latest
Phoenix raob had PWAT up to 1.44 inches and Tucson had 1.5 inches.
Despite the ample moisture, much of it was at mid and upper levels
through, limiting CAPE values. According to the 2 am SPC
mesoanalysis graphic, MLCAPE of consequence (over 500 j/kg) was
still over far SE Arizona with very low amounts in the central
deserts. 2 am radar continued to show showers spreading into south
central Arizona from the southeast and isolated thunderstorms are
possible but any convection that develops should stay on the weak
side into the morning hours. The convection is likely being aided by
weak vort maxes rotating into Arizona around the large scale upper
high. Should significant clouds and showers persist well into the
morning or the early afternoon, instability will again be limited
and storm activity tonight will suffer.
For the next few days, operational models such as the GFS and ECMWF
as well as GEFS data, call for the monsoonal circulation to remain
in place with little change from day to day. Moisture will remain
relatively plentiful, at least from a PWAT perspective as values
upwards of 1.5 inches will stay over much of the lower deserts to
the east of the lower Colorado river valley. Most of the CAPE of
consequence however is advertised to stay pretty much from Maricopa
county eastward each day, suggesting convective potential over the
southwest deserts will be limited, and minimal as you move into the
deserts of southeast California. Steering flow each day will stay
south to southeast but not overly strong, with 700-300mb layer winds
mostly between 10 and 15 knots each day. There will be occasional
vort maxes/weak inverted trofs rotating around the main upper high
and moving north across the central deserts but due to the small
scale of these features, they will not be handled very well by the
models and as such there will be low confidence in any particular
one of these small scale features. As such we will keep a rather low
grade monsoon forecast in place today through Wednesday with slight
chances for mainly afternoon and evening showers and thunderstorms
over the central lower deserts, with better chances over the higher
terrain east of Phoenix. Skies will be partly to mostly cloudy much
of the time, with the greatest amounts of sunshine likely during
later morning through mid afternoon each day. High temperatures will
stay near seasonal normals over south central Arizona today, then
gradually creep up each day with Phoenix approaching 110 by
Wednesday. It will be hotter over the far western deserts and over
SE California as the airmass will be drier there.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will at the
114 degree mark. Ouch! Current forecasts will keep Phoenix at or
above the 110 degree mark each day. At the moment it appears high
temperature will stay below excessive heat warning thresholds but
that could change depending upon just how dry we actually get, and
how high the heights become over the lower deserts.
&&
.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL:
Light showers will remain possible through the early afternoon hours
with light/variable winds and cigs AOA 10k ft. There is an enhanced
risk of gusty southeast winds and blowing dust this evening though
only enough confidence at this point to show a modest wind shift at
most terminals.
Southeast California/Southwest Arizona including KIPL and KBLH:
Scattered/broken high clouds will typical diurnal wind directions and
relatively light. Airmass expected to be too dry to support any
showers or thunderstorms over the next 24-36 hours.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Wednesday through Sunday...
Humidity values will be on the downward trend from Wednesday heading
into the weekend as moisture levels thin and temperatures increase.
Minimum afternoon humidity values will bottom-out in near 10 percent
below 4000` and 20-30 percent above 4000`. Thunderstorm activity,
which is not expected to be significant, will be greatest
Wednesday/Thursday over the mountains then decreasing into the
weekend. Modest at best chances for lower elevation rains. Except for
thunderstorm-driven outflow winds, typical diurnal patterns expected.
$$
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...CB/Vasquez
AVIATION...Iniguez
FIRE WEATHER...Iniguez
[top]
Area Forecast Discussion
National Weather Service Flagstaff AZ
430 AM MST MON JUL 18 2016
.update fire weather discussion.
.SYNOPSIS...Monsoon moisture will continue to bring a chance of
showers and thundertorms through Thursday. Strong high pressure
and drier air could result in a downturn in activity toward the
end of the week.
&&
.DISCUSSION...A strong and wide reaching high pressure system will
remain centered over the Oklahoma/Arkansas region through Thursday
before shifting back over the western states next weekend.
For today through Thursday...Due to the position of the high
southerly flow and monsoon moisture will remain over northern
Arizona. There should be some increase in moisture values over
Sunday so shower and thunderstorm activity is expected to be more
widespread. Instability and strength of any storms will be
inhibited by general mid to high level cloud cover and the fact
that the pattern doesn`t favor a decent push of low level
moisture. In other words, precipitation amounts will mostly remain
on the low to modest side.
From Friday onward...Models show strong high pressure aloft
building across Arizona into California. As a result, a drier air
mass will filter in from the west. Low to no grade monsoon
activity will be the result should this pattern materialize.
&&
.AVIATION...For the 12Z package...Primarily VFR conditions are
expected for the next 24 hours with bkn cigs aoa 14kft msl. til 17z
isolated -shra / tsra possible, then btwn 17z-02z sct-nmrs SHRA/TSRA
especially mountain areas. Brief visibility reductions and gusty
winds possible near storms. Precipitation coverage decreasing
after 02z Tues.
&&
.FIRE WEATHER...Monsoon moisture is increasing across the area.
Expect increasing showers and thunderstorm coverage. Gusty outflow
winds are probable from any storms or showers, especially today.
Storm motion today from south to north about 10 mph.
Tuesday through Friday...Monsoon moisture to remain over northern
Arizona, with shower and thunderstorm chances each day through
Thursday. Drier southwest flow may move back into northwest Arizona
starting Friday leading to decreasing storm chances there.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...McCollum
AVIATION...DL
FIRE WEATHER...DL
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Flagstaff AZ
430 AM MST MON JUL 18 2016
.update fire weather discussion.
.SYNOPSIS...Monsoon moisture will continue to bring a chance of
showers and thundertorms through Thursday. Strong high pressure
and drier air could result in a downturn in activity toward the
end of the week.
&&
.DISCUSSION...A strong and wide reaching high pressure system will
remain centered over the Oklahoma/Arkansas region through Thursday
before shifting back over the western states next weekend.
For today through Thursday...Due to the position of the high
southerly flow and monsoon moisture will remain over northern
Arizona. There should be some increase in moisture values over
Sunday so shower and thunderstorm activity is expected to be more
widespread. Instability and strength of any storms will be
inhibited by general mid to high level cloud cover and the fact
that the pattern doesn`t favor a decent push of low level
moisture. In other words, precipitation amounts will mostly remain
on the low to modest side.
From Friday onward...Models show strong high pressure aloft
building across Arizona into California. As a result, a drier air
mass will filter in from the west. Low to no grade monsoon
activity will be the result should this pattern materialize.
&&
.AVIATION...For the 12Z package...Primarily VFR conditions are
expected for the next 24 hours with bkn cigs aoa 14kft msl. til 17z
isolated -shra / tsra possible, then btwn 17z-02z sct-nmrs SHRA/TSRA
especially mountain areas. Brief visibility reductions and gusty
winds possible near storms. Precipitation coverage decreasing
after 02z Tues.
&&
.FIRE WEATHER...Monsoon moisture is increasing across the area.
Expect increasing showers and thunderstorm coverage. Gusty outflow
winds are probable from any storms or showers, especially today.
Storm motion today from south to north about 10 mph.
Tuesday through Friday...Monsoon moisture to remain over northern
Arizona, with shower and thunderstorm chances each day through
Thursday. Drier southwest flow may move back into northwest Arizona
starting Friday leading to decreasing storm chances there.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...McCollum
AVIATION...DL
FIRE WEATHER...DL
For Northern Arizona weather information visit
weather.gov/flagstaff
[top]
Area Forecast Discussion
National Weather Service Tucson AZ
340 AM MST MON JUL 18 2016
.SYNOPSIS...Adequate moisture will provide scattered mainly afternoon
and evening showers and thunderstorms through Wednesday. A slight
decrease in daily coverage of showers and thunderstorms should then
occur Thursday into next weekend.
&&
.DISCUSSION...The 330 am radar imagery showed a distinctive
circulation just west of Willcox, moving to the WNW. This MCV is
associated with decaying MCS that formed over eastern Cochise county
last night and produced areas of locally heavy rain. Douglas airport
recorded 1.75" last night which set a daily record and also ranks as
the 9th wettest July day on record.
The MCV will be one of several features that will have an impact on
todays forecast. Last nights MCS likely associated with a weak
disturbance aloft that moved across northern Chihuahua MX. Water
vapor was also showing an inverted trof approaching the Texas Big
Bend this morning. A challenging forecast indeed for the next 12-18
hours. One would go with the idea that after the morning activity
ends, that there will be lesser activity this afternoon due to
debris cloud cover slowly diminishing which cuts down on heating
thus being a few degrees cooler than Sunday. However both HRRR and
00z WRF NAM/GFS fire scattered storms this afternoon. Confidence is
low will this forecast.
Tomorrow likely will be another forecast challenge based on what
will transpire today. Again confidence is low.
Wednesday through next weekend will see a gradual decrease in
moisture and thus areal coverage of storms as the sub-tropical high
expands west into the eastern Pacific. Temperature warming up but
likely not as hot as the GFS would suggest if going by low-level
thickness numbers, which are higher than EC. Something to keep
watch.
&&
.AVIATION...VALID THRU 19/12Z.
Isolated to scattered SHRA/TSRA will occur through the period. Brief
wind gusts of 35-40 kts and MVFR conditions may occur with the
stronger TSRA. Outside of thunderstorm outflows, sfc wind will
generally be 8-12 kts. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...Plenty of moisture will remain in place this week
for daily chances of mainly afternoon and evening showers and
thunderstorms. A slight decrease in rain chances may occur late in
the week into next weekend. Outside of gusty thunderstorm/outflow
winds, expect typical diurnal 20-ft wind patterns each day. Stronger
gusts are possible through the Gila River Valley when winds are
northwesterly in direction.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
614 AM CDT MON JUL 18 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 313 AM CDT MON JUL 18 2016
An MCS moving through northwest MO has formed an outflow that is
currently pushing southwestward towards far northeast KS. A west to
southwesterly low level jet is intersecting this outflow, and is
responsible for additional storm development in that area. Those
storms may backbuild into far northeast KS in the next few hours
until the cold pool quits progressing or mixes out. There is also
increasing isentropic lift taking place in central KS. Storms have
formed along this axis of lift that stretches back into southwest
KS. The NAM shows this isentropic lift on the 310 K surface nosing
into northeast KS in the next few hours with the coverage most
likely staying isolated to scattered. Therefore have kept slight
chances across the northwest portions of the forecast area through
just after sunrise. How far east these showers and storms extend is
uncertain at this time. Several consecutive runs of the HRRR have
shown this activity reaching east central KS before it weakens as
the low level jet decreases. Given the HRRR is already off on storm
location means perhaps it might not get far into the forecast area
all together. Soundings show about 1500-2000 j/kg of mucape above
drier air in the lower levels and a weak nocturnal inversion. The
effective shear is also around 30 kt, which is marginal from
organization. If a storm were to realize this instability perhaps a
strong localized wind gust could not be ruled out within the
stronger cells.
Later today the temperatures will warm again into the mid 90s to
lower 100s with dew points in the upper 60s to lower 70s. This
combination will cause heat indices between 100-105 this
afternoon, and a heat advisory is in effect.
.LONG TERM...(Tuesday through Sunday)
Issued at 313 AM CDT MON JUL 18 2016
Heat indicies continue their climb through the week, with Tuesday
bringing another day in the 100-105 range, followed by a jump into
the 103-109 range by Wednesday and continuing in that range into
Friday. As a result, and in collaboration with neighbor offices,
have opted to carry a heat advisory through the week. With several
days of heat indicies above 100 by mid week, may need to upgrade
to a warning for the mid to late week time period, considering the
cumulative impacts of several days of heat. In short, outdoor
activities this week will require vigilance about the potential
impacts of several days of heat advisories. Please plan
accordingly.
EC and GFS both try to break down the ridge through the weekend as
an upper trof progresses across the US/Canadian border and sends a
front southward in its wake. EC is stronger and farther southward
with the upper trof, and therefore faster moving the boundary
into southern Kansas by late Saturday. The GFS has a slower
progression but does bring the front through on Sunday. Sensible
weather impacts would be an increasing chance for rain into
Sunday, and a break from the heat of the week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday Morning)
Issued at 612 AM CDT MON JUL 18 2016
VFR conditions expected through the taf period. There may be
occasional gusts around 20 mph during the day especially at MHK.
&&
.TOP Watches/Warnings/Advisories...
Heat Advisory from 1 PM this afternoon to 7 PM CDT Friday for
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Sanders
Area Forecast Discussion
National Weather Service Tucson AZ
325 PM MST MON JUL 18 2016
.SYNOPSIS...Adequate moisture will provide scattered mainly afternoon
and evening showers and thunderstorms through Wednesday. A slight
decrease in daily coverage of showers and thunderstorms should then
occur Thursday into this weekend. Expect near normal daytime
temperatures Tuesday followed by a pronounced warming trend later
this week.
&&
.DISCUSSION...Scattered to numerous showers and thunderstorms were
occurring generally from the Tohono O`odham Nation southeastward
into far southeast Pima County, Santa Cruz County, and extreme
southwest Cochise County at this time. This area is within a
northwest-to-southeast oriented axis of greatest instability as per
SPC hourly mesoscale analysis of MUCAPE. Other isolated showers and
thunderstorms were also occurring from southcentral Pinal County
eastward into western Graham County. Storm motions were mainly
northwest around 5-10 kts. IR satellite imagery depicted rapidly
cooling cloud tops during the past hour with the showers/tstms
across central Pima County.
Have favored the Univ of AZ WRF-NAM for precip chances tonight.
Thus, expect scattered to perhaps numerous showers/tstms across much
of the area this evening. The main concern given relatively slow
storm motions and precip water values of 1.25"-1.50" will be locally
heavy rainfall. Have maintained a slight chance of showers/tstms
late tonight for much of this forecast area. Have noted that the WRF-
NAM depicts precip-free conditions late tonight into mid-morning
Tuesday. Will defer to the evening shift to adjust PoPs perhaps
downward as necessary. Similar coverage of showers/tstms is expected
Tuesday afternoon/evening as deep (albeit still light) sely flow
aloft continues across the area. Scattered mainly afternoon/evening
showers/tstms will also occur Wednesday.
Thereafter, the 18/12Z GFS/ECMWF/CMC were similar versus their
respective solutions in depicting a gradual daily decrease in
showers/tstms to begin Thursday and continue into this weekend.
Given the continued ely mid-level flow, precip-free conditions area-
wide should not occur as earlier this month. However, moisture
should remain sufficient for isolated to scattered afternoon and
evening showers and thunderstorms Thursday through next Monday.
High temps Tuesday will remain quite close to seasonal normals. A
warming trend is forecast to begin Wednesday, and based on various
18/12Z guidance, high temps were increased several degs Thur-Sat
versus the previous forecast. At this time, appears that Friday will
be the hottest day although Saturday should be quite similar. A
moderation in daytime temps should then occur Sunday and Monday.
&&
.AVIATION...VALID THRU 20/00Z.
Isolated to scattered SHRA/TSRA will occur through the period, with
the best chances during the afternoon and evening hours. Brief wind
gusts of 35-40 kts and MVFR conditions may occur with the stronger
TSRA. Outside of thunderstorm outflows, sfc wind will generally be
less than 12 kts through Tuesday afternoon. Aviation discussion not
updated for TAF amendments.
&&
.FIRE WEATHER...Ample moisture will ensure daily chances of mainly
afternoon and evening showers and thunderstorms this week. A slight
decrease in rain chances will occur late in the week into the
weekend along with an increase in daytime temperatures. Outside of
gusty thunderstorm/outflow winds, expect typical diurnal 20-ft wind
patterns each day at mainly less than 15 mph.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
DISCUSSION...Francis
AVIATION/FIRE WEATHER...French
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
[top]
Area Forecast Discussion
National Weather Service Flagstaff AZ
250 PM MST MON JUL 18 2016
.SYNOPSIS...Monsoon moisture will continue to bring a chance of
showers and thundertorms through Thursday. Strong high pressure
and drier air could result in a downturn in activity toward the
end of the week.
&&
.DISCUSSION...
The monsoon circulation has brought plentiful atmospheric moisture
back into to the area...with precipitable water values now up to
around 1.0" at KFLG. Instability has been somewhat limited...but
scattered thunderstorms have formed with a few locally heavy
showers, mainly over the higher terrain. Little change in the
overall pattern is anticipated through Thursday with the strong
ridge of high pressure in place over the Southern Plains and moist
southerly flow over Arizona, providing the environment for daily
thunderstorm activity across the forecast area. Storms will move a
bit slower Tuesday through Thursday, leading to a somewhat greater
chance for heavy rainfall accumulations.
Friday through Sunday...forecast models continue to show the
flattening of the ridge over the southern Rockies, and a decrease in
thunderstorm activity Friday through Sunday as drier air filters in
from the west.
&&
.AVIATION...For the 00Z package...Sct shra/tsra expected to
continue through 03z...with isold -shra/-tsra continuing overnight.
Sct shra/tsra will redevelop after 18Z Tuesday...with storms most
numerous over the higher terrain. Expect visibility reductions and
gusty winds near storms. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...Expect another round of thunderstorms over the
forecast area Tuesday and Wednesday. Storm motion will generally be
from the south to north 5-10 mph.
Thursday through Saturday...Scattered thunderstorms will persist
across the area on Thursday. Drier air filtering into Arizona from
the west will bring a decrease in thunderstorm activity on Friday
and Saturday...with minimum RH`s dropping back into the teens to the
north and west of Flagstaff.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...Bohlin/BAK
AVIATION...BAK
FIRE WEATHER...BAK
For Northern Arizona weather information visit
weather.gov/flagstaff
[top]
Area Forecast Discussion
National Weather Service Phoenix AZ
200 PM MST MON JUL 18 2016
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle, and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Tonight...Elevated amounts of monsoon moisture have now securely
covered most of AZ. Athough thermodynamics are there for a few
afternoon and evening showers and thunderstorms over our forecast
area in south central AZ, this region seems to be inbetween upper
level forcing mechanisms in currently working in northern and
southern AZ.
With the advent of a fairly strong and unseasonably cold Pacific
trof moving into the Pacific northwest, a rather strong
southwesterly Jetstream maximum has developed over portions of
eastern Nevada and Utah. Accelerating winds aloft, from lighter
winds in northern AZ into the Utah flow, has developed an area of
upper level speed divergence and resulting convection. To our south
near the Mexican border, the approaching massive inverted trof,
clearly seen in water vapor imagery over the Mexican state of
Chihuahua, is spreading leading edge upper level difluence. Our
portions of south central AZ, including areas near Phoenix, are
under a relatively stable upper level anti-cyclonic flow regime.
Therefore a low grade monsoon forecast is expected for the remainder
of this afternoon and evening, i.e. a slight chance of showers and
thunderstorms. This forecast is excluding the possibility of copious
amounts of convective debris clouds from southern AZ moving north
toward Phoenix tonight, and causing the possibility of showers and
thunderstorms similar to late Sunday night. So far model forecasts
are minimizing this possibility.
Tuesday...our office staff eyes are now transfixed on the massive
inverted trof seen in water vapor imagery over north central Mexico.
Models the past two days have resolved this feature very well at the
300/250 mb level, and latest model forecasts continue the trend of
moving the feature bodily into southern AZ, although in a weakened
form later Tuesday and Tuesday night. Current model forecast are
minimizing the effect of this system in south central AZ, including
nearby Phoenix and surrounding areas. From a fundamental stand point
this is questionable. Strong differential heating and with weakness
aloft normally results in an enhanced threat for storms that can
last well into the evening hours. For now we will go with our
instincts and raise precip probability a bit in south central AZ for
late Tuesday and Tuesday night, with even a slight chance going into
Wednesday morning.
Wednesday...Monsoon moisture will be still be entrenched over the
region. With mid/upper level disturbances should depart the area,
resulting in another low grade monsoon forecast for Wednesday
afternoon and evening.
Thursday through Monday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures would be much higher. Therefore
afternoon desert temperatures are forecast to be above the 110
degree mark, but approaching 115 over the driest low humidity area
of southeast CA.
&&
.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL:
Timing wind shifts and the potential for gusty outflow winds
and localized blowing dust will be the primary aviation concerns
through Tuesday morning. Some variability about a southerly wind
direction is likely again this afternoon, though eventually should
favor southwest by the evening. Thunderstorms forming over SE AZ
should move north towards the Phoenix area late in the afternoon
with gusty outflow winds preceding them.
While the threat of a storm directly affecting an airport is
better than Sunday, probabilities are still quite low with better
chances of localized blowing dust and more widespread lofted dust and
haze affecting slantwise visibilities. Only modest confidence
exists timing outflow wind shifts into terminal sites between 02Z-
04Z. Otherwise, developing cigs in a 10K-15K ft range look likely
from decaying storms to the south.
Southeast California/Southwest Arizona including KIPL and KBLH:
Minimal aviation concerns through Tuesday morning with storm activity
remaining well east into central AZ. Under mostly clear skies, sfc
winds will favor a southerly direction, though will be more variable
at KIPL after sunset. A few higher gusts will be possible, but speeds
should generally remain at or below 15kt.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Thursday through Monday...
Temperatures will trend back into an above normal range through
the weekend as better quality moisture partially scours
out.Thunderstorm and wetting rain chances dwindle substantially
and become almost exclusively limited to higher terrain north and
east of Phoenix. Consequently, afternoon humidity levels near a 15-
30 percent range during the middle of the week will fall closer to a
10-25 percent range into the weekend. Outside of isolated gusty
winds surrounding any thunderstorms, directions will favor an
upslope component in the afternoon with gustiness around terrain
features and light overnight valley drainage.
&&
.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...Vasquez
FIRE WEATHER...MO
Area Forecast Discussion
National Weather Service Phoenix AZ
1230 PM MST MON JUL 18 2016
...Updated Aviation and Fire Weather...
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Woohoo, the monsoon moisture boundary raced north past Phoenix over
night and this morning was seen pushing up against the higher
elevations of the Mogollon Rim. In other words the southern half of
AZ was in the monsoon moisture soup, and noted by the relatively low
afternoon convective trigger temperatures at a few locations. For
example, based on this mornings weather balloon soundings, the
convective trigger temp at Phoenix is 99 deg F, 97 at Tucson, and 92
deg at Globe/Miami (elevation 3-4 thsd ft msl). Even though the
afternoon thermodynamics are there, the flow aloft has, and will
remain anti-cyclonic and relatively stable today and tonight. In
other words, the situation for today favors low topped afternoon
convection, mostly in the mountains with possible outflows toward
the deserts sparking an isolated desert storm, with convection
dissipating quickly after dark, unless.
Unless like last night, a surge of convective debris clouds from
southeast AZ spread north, creating a well saturated mid level
airmass that a gravity wave sparked a few showers and thunderstorms
in the Phoenix area after midnight. The gravity wave conclusion was
derived from high speed satellite imagery loops.
Beyond today, our office staff eyes are now on the massive inverted
trof seen in water vapor imagery over the north central Mexican
state of Chihuahua. Models the past two days have resolved this
feature very well at the 300/250 mb level, and is forecast to move
into southeast AZ on Tuesday.
For now the low grade monsoon forecast, meaning slight chance of
showers and thunderstorms over the south central AZ deserts and
mountains look ok for now. We will see how the new models handle
Tuesdays inverted trof since model guidance will have incorporated
the Chihuahua weather balloon sounding that is launched once per day
at 12z.
.Previous discussion...503 AM MST...
The weather pattern has finally allowed the typical monsoonal
circulation to return to the area as the combination of troffing
along the Pacific northwest coast and upper ridging over the central
CONUS has allowed southerly to southeasterly flow aloft to set up
across Arizona. This favorable flow has advected considerable
amounts of monsoon moisture into the lower deserts; the latest
Phoenix raob had PWAT up to 1.44 inches and Tucson had 1.5 inches.
Despite the ample moisture, much of it was at mid and upper levels
through, limiting CAPE values. According to the 2 am SPC
mesoanalysis graphic, MLCAPE of consequence (over 500 j/kg) was
still over far SE Arizona with very low amounts in the central
deserts. 2 am radar continued to show showers spreading into south
central Arizona from the southeast and isolated thunderstorms are
possible but any convection that develops should stay on the weak
side into the morning hours. The convection is likely being aided by
weak vort maxes rotating into Arizona around the large scale upper
high. Should significant clouds and showers persist well into the
morning or the early afternoon, instability will again be limited
and storm activity tonight will suffer.
For the next few days, operational models such as the GFS and ECMWF
as well as GEFS data, call for the monsoonal circulation to remain
in place with little change from day to day. Moisture will remain
relatively plentiful, at least from a PWAT perspective as values
upwards of 1.5 inches will stay over much of the lower deserts to
the east of the lower Colorado river valley. Most of the CAPE of
consequence however is advertised to stay pretty much from Maricopa
county eastward each day, suggesting convective potential over the
southwest deserts will be limited, and minimal as you move into the
deserts of southeast California. Steering flow each day will stay
south to southeast but not overly strong, with 700-300mb layer winds
mostly between 10 and 15 knots each day. There will be occasional
vort maxes/weak inverted trofs rotating around the main upper high
and moving north across the central deserts but due to the small
scale of these features, they will not be handled very well by the
models and as such there will be low confidence in any particular
one of these small scale features. As such we will keep a rather low
grade monsoon forecast in place today through Wednesday with slight
chances for mainly afternoon and evening showers and thunderstorms
over the central lower deserts, with better chances over the higher
terrain east of Phoenix. Skies will be partly to mostly cloudy much
of the time, with the greatest amounts of sunshine likely during
later morning through mid afternoon each day. High temperatures will
stay near seasonal normals over south central Arizona today, then
gradually creep up each day with Phoenix approaching 110 by
Wednesday. It will be hotter over the far western deserts and over
SE California as the airmass will be drier there.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will at the
114 degree mark. Ouch! Current forecasts will keep Phoenix at or
above the 110 degree mark each day. At the moment it appears high
temperature will stay below excessive heat warning thresholds but
that could change depending upon just how dry we actually get, and
how high the heights become over the lower deserts.
&&
.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL:
Timing wind shifts and the potential for gusty outflow winds
and localized blowing dust will be the primary aviation concerns
through Tuesday morning. Some variability about a southerly wind
direction is likely again this afternoon, though eventually should
favor southwest by the evening. Thunderstorms forming over SE AZ
should move north towards the Phoenix area late in the afternoon
with gusty outflow winds preceding them.
While the threat of a storm directly affecting an airport is
better than Sunday, probabilities are still quite low with better
chances of localized blowing dust and more widespread lofted dust and
haze affecting slantwise visibilities. Only modest confidence
exists timing outflow wind shifts into terminal sites between 02Z-
04Z. Otherwise, developing cigs in a 10K-15K ft range look likely
from decaying storms to the south.
Southeast California/Southwest Arizona including KIPL and KBLH:
Minimal aviation concerns through Tuesday morning with storm activity
remaining well east into central AZ. Under mostly clear skies, sfc
winds will favor a southerly direction, though will be more variable
at KIPL after sunset. A few higher gusts will be possible, but speeds
should generally remain at or below 15kt.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Thursday through Monday...
Temperatures will trend back into an above normal range through
the weekend as better quality moisture partially scours
out.Thunderstorm and wetting rain chances dwindle substantially
and become almost exclusively limited to higher terrain north and
east of Phoenix. Consequently, afternoon humidity levels near a 15-
30 percent range during the middle of the week will fall closer to a
10-25 percent range into the weekend. Outside of isolated gusty
winds surrounding any thunderstorms, directions will favor an
upslope component in the afternoon with gustiness around terrain
features and light overnight valley drainage.
&&
.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...Vasquez/CB/Vasquez
AVIATION...MO
FIRE WEATHER...MO
Area Forecast Discussion
National Weather Service Phoenix AZ
1230 PM MST MON JUL 18 2016
...Updated Aviation and Fire Weather...
.SYNOPSIS...
An increase in clouds and humidity can be expected during the next
few days along with a slight chance of showers and thunderstorms,
mainly east of the Lower Colorado River Valley. High temperatures
will also be a bit cooler. Storm chances on the lower deserts will
be slight, with better chances over the higher terrain and over
southeast Arizona. During the latter half of the week, storm chances
will dwindle and temperatures will increase to above normal levels.
&&
.DISCUSSION...
Woohoo, the monsoon moisture boundary raced north past Phoenix over
night and this morning was seen pushing up against the higher
elevations of the Mogollon Rim. In other words the southern half of
AZ was in the monsoon moisture soup, and noted by the relatively low
afternoon convective trigger temperatures at a few locations. For
example, based on this mornings weather balloon soundings, the
convective trigger temp at Phoenix is 99 deg F, 97 at Tucson, and 92
deg at Globe/Miami (elevation 3-4 thsd ft msl). Even though the
afternoon thermodynamics are there, the flow aloft has, and will
remain anti-cyclonic and relatively stable today and tonight. In
other words, the situation for today favors low topped afternoon
convection, mostly in the mountains with possible outflows toward
the deserts sparking an isolated desert storm, with convection
dissipating quickly after dark, unless.
Unless like last night, a surge of convective debris clouds from
southeast AZ spread north, creating a well saturated mid level
airmass that a gravity wave sparked a few showers and thunderstorms
in the Phoenix area after midnight. The gravity wave conclusion was
derived from high speed satellite imagery loops.
Beyond today, our office staff eyes are now on the massive inverted
trof seen in water vapor imagery over the north central Mexican
state of Chihuahua. Models the past two days have resolved this
feature very well at the 300/250 mb level, and is forecast to move
into southeast AZ on Tuesday.
For now the low grade monsoon forecast, meaning slight chance of
showers and thunderstorms over the south central AZ deserts and
mountains look ok for now. We will see how the new models handle
Tuesdays inverted trof since model guidance will have incorporated
the Chihuahua weather balloon sounding that is launched once per day
at 12z.
.Previous discussion...503 AM MST...
The weather pattern has finally allowed the typical monsoonal
circulation to return to the area as the combination of troffing
along the Pacific northwest coast and upper ridging over the central
CONUS has allowed southerly to southeasterly flow aloft to set up
across Arizona. This favorable flow has advected considerable
amounts of monsoon moisture into the lower deserts; the latest
Phoenix raob had PWAT up to 1.44 inches and Tucson had 1.5 inches.
Despite the ample moisture, much of it was at mid and upper levels
through, limiting CAPE values. According to the 2 am SPC
mesoanalysis graphic, MLCAPE of consequence (over 500 j/kg) was
still over far SE Arizona with very low amounts in the central
deserts. 2 am radar continued to show showers spreading into south
central Arizona from the southeast and isolated thunderstorms are
possible but any convection that develops should stay on the weak
side into the morning hours. The convection is likely being aided by
weak vort maxes rotating into Arizona around the large scale upper
high. Should significant clouds and showers persist well into the
morning or the early afternoon, instability will again be limited
and storm activity tonight will suffer.
For the next few days, operational models such as the GFS and ECMWF
as well as GEFS data, call for the monsoonal circulation to remain
in place with little change from day to day. Moisture will remain
relatively plentiful, at least from a PWAT perspective as values
upwards of 1.5 inches will stay over much of the lower deserts to
the east of the lower Colorado river valley. Most of the CAPE of
consequence however is advertised to stay pretty much from Maricopa
county eastward each day, suggesting convective potential over the
southwest deserts will be limited, and minimal as you move into the
deserts of southeast California. Steering flow each day will stay
south to southeast but not overly strong, with 700-300mb layer winds
mostly between 10 and 15 knots each day. There will be occasional
vort maxes/weak inverted trofs rotating around the main upper high
and moving north across the central deserts but due to the small
scale of these features, they will not be handled very well by the
models and as such there will be low confidence in any particular
one of these small scale features. As such we will keep a rather low
grade monsoon forecast in place today through Wednesday with slight
chances for mainly afternoon and evening showers and thunderstorms
over the central lower deserts, with better chances over the higher
terrain east of Phoenix. Skies will be partly to mostly cloudy much
of the time, with the greatest amounts of sunshine likely during
later morning through mid afternoon each day. High temperatures will
stay near seasonal normals over south central Arizona today, then
gradually creep up each day with Phoenix approaching 110 by
Wednesday. It will be hotter over the far western deserts and over
SE California as the airmass will be drier there.
Thursday through Sunday...monsoon moisture is forecast to thin a
little as drier air from New Mexico and Colorado mix over the area.
At the same time atmospheric height and thickness values increase
dramatically over the region, and if it weren`t for remnant monsoon
moisture, afternoon temperatures be much higher. The driest areas
Thursday through Sunday will be southeast California where afternoon
temperatures at Imperial, El Centro, and Blythe will at the
114 degree mark. Ouch! Current forecasts will keep Phoenix at or
above the 110 degree mark each day. At the moment it appears high
temperature will stay below excessive heat warning thresholds but
that could change depending upon just how dry we actually get, and
how high the heights become over the lower deserts.
&&
.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL:
Timing wind shifts and the potential for gusty outflow winds
and localized blowing dust will be the primary aviation concerns
through Tuesday morning. Some variability about a southerly wind
direction is likely again this afternoon, though eventually should
favor southwest by the evening. Thunderstorms forming over SE AZ
should move north towards the Phoenix area late in the afternoon
with gusty outflow winds preceding them.
While the threat of a storm directly affecting an airport is
better than Sunday, probabilities are still quite low with better
chances of localized blowing dust and more widespread lofted dust and
haze affecting slantwise visibilities. Only modest confidence
exists timing outflow wind shifts into terminal sites between 02Z-
04Z. Otherwise, developing cigs in a 10K-15K ft range look likely
from decaying storms to the south.
Southeast California/Southwest Arizona including KIPL and KBLH:
Minimal aviation concerns through Tuesday morning with storm activity
remaining well east into central AZ. Under mostly clear skies, sfc
winds will favor a southerly direction, though will be more variable
at KIPL after sunset. A few higher gusts will be possible, but speeds
should generally remain at or below 15kt.
Aviation Discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Thursday through Monday...
Temperatures will trend back into an above normal range through
the weekend as better quality moisture partially scours
out.Thunderstorm and wetting rain chances dwindle substantially
and become almost exclusively limited to higher terrain north and
east of Phoenix. Consequently, afternoon humidity levels near a 15-
30 percent range during the middle of the week will fall closer to a
10-25 percent range into the weekend. Outside of isolated gusty
winds surrounding any thunderstorms, directions will favor an
upslope component in the afternoon with gustiness around terrain
features and light overnight valley drainage.
&&
.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...Vasquez/CB/Vasquez
AVIATION...MO
FIRE WEATHER...MO
Area Forecast Discussion
National Weather Service Flagstaff AZ
1004 AM MST MON JUL 18 2016
.SYNOPSIS...Monsoon moisture will continue to bring a chance of
showers and thundertorms through Thursday. Strong high pressure
and drier air could result in a downturn in activity toward the
end of the week.
&&
.DISCUSSION...The subtropical ridge remains in a favorable
position for moisture advection into Arizona through Friday. This
translates into a moderate grade Monsoon with good chances for
showers and thunderstorms each day. A few storms will develop in
the overnight periods as a few upper level 200-300mb disturbances
roll across the state.
We sent out a quick update to increase shower chances this
evening. Otherwise the forecast grids look good.
&&
.PREV DISCUSSION /430 AM MST/...
For today through Thursday...Due to the position of the high
southerly flow and monsoon moisture will remain over northern
Arizona. There should be some increase in moisture values over
Sunday so shower and thunderstorm activity is expected to be more
widespread. Instability and strength of any storms will be
inhibited by general mid to high level cloud cover and the fact
that the pattern doesn`t favor a decent push of low level
moisture. In other words, precipitation amounts will mostly remain
on the low to modest side.
From Friday onward...Models show strong high pressure aloft
building across Arizona into California. As a result, a drier air
mass will filter in from the west. Low to no grade monsoon
activity will be the result should this pattern materialize.
&&
.AVIATION...For the 18Z package...sct-nmrs shra/tsra expected to
develop this afternoon...continuing through 03z. Brief visibility
reductions and gusty winds possible near storms. isold-sct -shra
will continue aft 05Z. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...Monsoon moisture is increasing across the area.
Expect increasing showers and thunderstorm coverage. Gusty outflow
winds are probable from any storms or showers, especially today.
Storm motion today from south to north about 10 mph.
Tuesday through Friday...Monsoon moisture to remain over northern
Arizona, with shower and thunderstorm chances each day. Winds may
become erratic and gusty near thunderstorms.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...Bohlin/McCollum
AVIATION...BAK
FIRE WEATHER...DL
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Tucson AZ
915 AM MST MON JUL 18 2016
.SYNOPSIS...Adequate moisture will provide scattered mainly afternoon
and evening showers and thunderstorms through Wednesday. A slight
decrease in daily coverage of showers and thunderstorms should then
occur Thursday into the upcoming weekend.
&&
.DISCUSSION...Isolated showers were occurring in western Pima County
east of Ajo at this time. Otherwise, visible satellite imagery
depicted mostly clear skies to partly cloudy skies from Tucson
westward into western Pima County, and mostly clear skies across
eastern sections. Ample moisture exists with dewpoints at lower
elevations valid 16Z ranging from the mid 50s-lower 60s. 18/12Z KTWC
sounding total precip water value of 1.50" was about 0.15" higher
versus 24 hours ago. 18/12Z upper air plots depicted a broad ridge
over the southern CONUS, with a 597 DM high centered over northern
Mississippi. Meanwhile, a deep upper trough was over the Pacific NW,
and deep easterly/southeasterly flow prevailed across southeast AZ.
Given the greater extent of clearing skies especially across eastern
sections versus Sunday morning, am inclined to expect that shower/
tstm development later this morning will occur across favored ranges
such as the Chiricahua Mountains. The 18/14Z HRRR supports this
notion, the showers/tstms should migrate wwd/nwwd this afternoon.
Quick glance at the 18/12Z Univ. of AZ WRF-NAM suggests shower/tstm
development may also occur further westward by 19Z, and favor
locales from Nogales to Kitt Peak. Water vapor imagery depicts a
cyclonic twist approaching this area from the southeast over central
Sonora Mexico. A much larger cyclonic circulation was south of the
Texas Big Bend, or far eastern Chihuahua Mexico. This system may
have more influence for this forecast area Tuesday.
At any rate and without a further recitation of various NWP models,
expect scattered to perhaps numerous showers and thunderstorms this
afternoon and evening. The lowest coverage should occur across
western Pima County where only isolated showers/tstms are expected.
The main concern this afternoon/evening will be the potential for
locally heavy rainfall and brief strong wind gusts that may approach
severe thresholds. A slight chance of showers/tstms continues for
much of the area late tonight.
High temps this afternoon will be quite similar to temps achieved
Sunday, or perhaps generally a couple of degs lower depending upon
location.
May make some minor PoP adjustments for this afternoon/evening, but
this will not affect the overall scenario. Please refer to the
additional sections for further detail.
&&
.AVIATION...VALID THRU 19/18Z.
Isolated -SHRA mainly west of KTUS this morning, then scattered to
numerous -TSRA/-SHRA this afternoon and evening. The favored locales
will be from KTUS vicinity east and south to the New Mexico/
International borders. Forecast confidence is sufficiently high to
include VCTS in the KDUG/KOLS TAFs this afternoon and evening. VCTS
may be delayed at KTUS until after 20/00Z. Isolated -SHRA and
possible -TSRA to continue late tonight/early Tuesday morning.
Outside of thunderstorm outflows, surface wind will generally be
variable in direction less than 12 kts thru the period. Aviation
discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Ample moisture and a favorable flow regime will
maintain the daily cycle of scattered to perhaps numerous showers
and thunderstorms through Wednesday. The bulk of this activity will
occur during the afternoon and evening hours, and a slight chance of
showers and thunderstorms will continue during the overnight hours.
Thereafter, a gradual decrease in thunderstorm coverage is expected
Thursday into the upcoming weekend. Outside of gusty thunderstorm
outflows, 20-foot winds will be terrain driven and mostly less than
15 mph.
&&
.PREV DISCUSSION /340 AM MST/...The 330 am radar imagery showed a
distinctive circulation just west of Willcox, moving to the WNW.
This MCV is associated with decaying MCS that formed over eastern
Cochise county last night and produced areas of locally heavy rain.
Douglas airport recorded 1.75" last night which set a daily record
and also ranks as the 9th wettest July day on record.
The MCV will be one of several features that will have an impact on
todays forecast. Last nights MCS likely associated with a weak
disturbance aloft that moved across northern Chihuahua MX. Water
vapor was also showing an inverted trof approaching the Texas Big
Bend this morning. A challenging forecast indeed for the next 12-18
hours. One would go with the idea that after the morning activity
ends, that there will be lesser activity this afternoon due to
debris cloud cover slowly diminishing which cuts down on heating
thus being a few degrees cooler than Sunday. However both HRRR and
00z WRF NAM/GFS fire scattered storms this afternoon. Confidence is
low will this forecast.
Tomorrow likely will be another forecast challenge based on what
will transpire today. Again confidence is low.
Wednesday through next weekend will see a gradual decrease in
moisture and thus areal coverage of storms as the sub-tropical high
expands west into the eastern Pacific. Temperature warming up but
likely not as hot as the GFS would suggest if going by low-level
thickness numbers, which are higher than EC. Something to keep
watch.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
333 PM CDT MON JUL 18 2016
.SHORT TERM...(This Evening through Tuesday)
Issued at 329 PM CDT MON JUL 18 2016
At 20Z, water vapor imagery shows a cloud band with moisture
streaming into the Central Rockies with another cloud band stretched
from the northern Central Plains into the Ohio Valley up through the
New England States. Some storms still along the stationary boundary
at the surface into northwestern MO and extreme southeastern IA.
Storms also beginning to fire over the foothills of the Rockies into
the panhandle of Nebraska.
In northeastern Kansas, forecasting a mostly dry period in the short
term as heights continue to rise steadily overnight into the day on
Tuesday. An MCS may develop overnight associated with the storms
previously mentioned over the Rockies. These should stay to the
north of the outlook area tonight though as the LLJ convergence is
focused to our northwest. Only the NAM brings some of this activity
close to the area with all the other short term guidance taking the
storms on a northerly track into northern Nebraska and northwestern
Iowa overnight. Therefore, not expecting much if any influence from
a cold outflow to impact our area even though there is a brief
period of isentropic lift that advects over the the region on the
315K to 320K surface. Lack of mid level moisture should keep storms
to the north. That said, do expect temperatures to increase again
tomorrow into the mid to upper 90s with dewpoints into the upper 60s
and low 70s. This should continue to put heat index values into the
105F range while lowest heat index values will be at or above 75F.
Have kept heat advisory going for the evening and have upgraded to a
heat warning starting Tuesday afternoon as many days of at least
heat advisory heat index values are expected. The bottom line is
the heat will be the main forecast concern through the period.
.LONG TERM...(Tuesday Night through Monday)
Issued at 329 PM CDT MON JUL 18 2016
Tuesday night through Thursday...
With upper high centered over the Southern/Central Plains during
this period, and no real low-level convergence features expected
to impact eastern KS, expect dry weather to continue. With
dewpoints from the upper 60s to mid 70s, and afternoon high
temperatures in the 96 to 103 degree range, afternoon heat indices
should be in the 103 to 108 degree range. Overnight lows are only
expected to fall to the mid to upper 70s.
Thursday Night through Monday...
A stout upper-level ridge will continue to be center of the central
United States through the end of the week. High temperatures will
soar into the upper 90s and lower 100s Friday afternoon. These very
hot temperatures coupled with high dewpoints, heat indices will
range from 105 to 110 degrees (possibly warmer). Saturday becomes a
bit tricky as both the EC and GFS bring a weak cold front through
portions of the area. Not only would it "cool" temperatures back
into the lower to middle 90s, but precip chances also increase. The
front appears to stall out in the vicinity of the outlook area for
the remainder of the weekend. Guidance suggests weak 500MB waves
will traverse the CWA along the surface boundary. Therefore, have at
least slight chance PoPs across the area, along with cooler
temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1227 PM CDT MON JUL 18 2016
For the 18Z TAFs, expect VFR conditions to prevail throughout the
period. Winds should slowly veer to a more SSE component into the
afternoon and evening. Slightly stronger winds near KMHK until
around the 01Z time frame.
&&
.TOP Watches/Warnings/Advisories...
Excessive Heat Warning from 1 PM Tuesday to 7 PM CDT Friday for
KSZ008>012-020>024-026-034>040-054>056-058-059.
Heat Advisory until 1 PM CDT Tuesday for KSZ008>012-020>024-026-
034>040-054>056-058-059.
&&
$$
SHORT TERM...Drake
LONG TERM...Baerg/GDP
AVIATION...Drake
[top]
Area Forecast Discussion
National Weather Service Wichita KS
311 PM CDT MON JUL 18 2016
.SYNOPSIS...
Issued at 311 PM CDT Mon Jul 18 2016
In the upper levels, water vapor imagery shows one shortwave
tracking across western Quebec with another impulse rotating over
the Pacific NW. Meanwhile, ridging is in place over the Rockies
into the Plains. At the surface, weak lee troughing is in place
with a weak front extending across northern MO into southern
Nebraska.
&&
.SHORT TERM...(This evening through Friday)
Issued at 311 PM CDT Mon Jul 18 2016
The main theme for the next few days will be for
the upper ridge to continue to build and expand over the Plains
through Fri. This will allow for plenty of sun and a warming
trend. Temps Tue look like the "coolest" through at least Fri
before the more serious heat starts Wed and continues through the
end of the work week. Should start to see more widespread highs at
or above 100 by Wed. The only good news is that we should start
to see afternoon dew points mix out for mid-late week which should
limit the 110+ heat indices. Due to the prolonged period of
100-105+ heat, will continue with heat headlines along and east
of I-135.
.LONG TERM...(Saturday through Monday)
Issued at 311 PM CDT Mon Jul 18 2016
Upper pattern will slowly start to flatten out starting Sat and
continue into the start of the work week. There is also some
model agreement in some shortwave energy sliding across the
northern Plains and into the western Great Lakes region by Sun
which may try and push a front into northern Kansas. In addition,
the more zonal flow will allow some of the weak impulses to track
over the area which may spark off a few storms. Confidence in
storm chances through these periods is extremely low as models
will have a hard time resolving these smaller scale features this
far out.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1231 PM CDT Mon Jul 18 2016
Weak low pressure was centered near Hays at 1730Z. This was along
a quasi-stationary boundary that extended from KGKC-KHYS.
Mainly a wind forecast over the next 24 hours as a dome of upper
level high pressure suppresses storm development across the area.
Winds will primarily be from the south to southwest at 10-20 knots
through the period. Cigs and vsbys VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 73 96 75 100 / 0 0 0 0
Hutchinson 74 97 75 100 / 0 0 0 0
Newton 74 95 75 99 / 0 0 0 0
ElDorado 74 95 75 98 / 0 0 0 0
Winfield-KWLD 74 95 75 99 / 0 0 0 0
Russell 73 98 75 102 / 10 0 0 0
Great Bend 73 98 74 101 / 0 0 0 0
Salina 75 97 76 102 / 10 10 0 0
McPherson 73 97 75 100 / 0 0 0 0
Coffeyville 74 95 75 96 / 0 0 0 0
Chanute 74 94 74 95 / 0 0 0 0
Iola 73 94 74 95 / 10 0 0 0
Parsons-KPPF 73 94 74 95 / 0 0 0 0
&&
.ICT Watches/Warnings/Advisories...
Heat Advisory until 8 PM CDT Friday for KSZ068>070-083-092>096-
098>100.
Excessive Heat Warning from noon Tuesday to 8 PM CDT Friday for
KSZ049-051>053-070>072.
Heat Advisory until noon CDT Tuesday for KSZ049-051>053-071-072.
&&
$$
SHORT TERM...RBL
LONG TERM...RBL
AVIATION...KRC
[top]
Area Forecast Discussion
National Weather Service Goodland KS
205 PM MDT MON JUL 18 2016
.SHORT TERM...(This afternoon through Tuesday)
Issued at 147 PM MDT Mon Jul 18 2016
Early afternoon satellite and RAP upper level analysis shows large
scale ridge entrenched across the central US, with monsoonal flow
in across through the central Rockies. A shortwave trough is
currently rotating into northern Colorado/southern Wyoming with
thunderstorms activity initiating in the higher terrain. A warm
front is slowly progressing northward over our CWA and is still
roughly south of I-70.
Early this afternoon-Tonight: Warm front has been slower to lift
north than models had previously indicated, however a strong CAP in
place is limiting initiation within frontal zone. Thunderstorm
activity may still initiate as the front lifts north and
thunderstorms in Colorado may also begin to sneak into our far west
before main area of thunderstorms develops this evening. As the
shortwave moves out of the Rockies into western Nebraska this should
help speed up the movement on the warm front and by 00z this feature
should be near the northern part of our CWA. Higher resolution
models support thunderstorms merging into a cluster or complex as
LLJ increases this evening and then tracking over our far northwest
and this is where I placed highest PoPs.
There is a deep/moist air mass in place with PWATs exceeding 1.0"
and Tds (within frontal zone) in the 60-70 range. Thunderstorm
motions are expected to be around 15 kt and east-southeast flow
overrunning the frontal zone could lead to training of thunderstorm
activity. This raises the possibility for locally heavy rainfall
amounts and at least a localized risk for flooding in our northwest.
Initially CAPE will be favorable for severe thunderstorms, however
deep layer sheer is very marginal and main CAPE axis will trend
northward with front.
Tuesday: Ridge continues to amplify shifting main flow further west
away from our CWA. Some guidance is still hinting at isolated
thunderstorms moving into northwest portions of Yuma county, however
confidence is not high this will make it this far east. Slight
chance PoPs were maintained for now. Temperatures will trend upwards
with strengthening of the ridge and increasing southerly flow with
high temperatures at least in the upper 90s for most locations and
near 100 (to the low 100s) in our north and east. Heat index values
appear to remain near 100F due to slightly lower Td values, so will
hold off on any highlights.
.LONG TERM...(Tuesday night through Monday)
Issued at 205 PM MDT Mon Jul 18 2016
Hot temperatures are anticipated during the longterm period, with
high pressure impacting the region into the weekend. Midweek appears
to be mainly dry while precipitation chances persist throughout the
extended.
Tuesday night through Thursday night: High pressure remains centered
over the CONUS and ridging dominates the pattern through midweek.
Could see isolated thunderstorms in the northwestern portion of the
area each afternoon/evening Tuesday and Wednesday as monsoonal
moisture wraps around the western side of the ridge. The high
pressure elongates over the southern half of the country on
Thursday. Thunderstorm chances return to the region in the evening
as the ridge begins to flatten.
Friday through Monday: At the end of the work week, a shortwave
pushes from the Pacific Northwest towards the northern Plains. This
disturbance sends a cold front south Friday night into Saturday,
bringing increased thunderstorm chances on Saturday and slightly
cooler temperatures for the weekend/early next week. The ridge
retreats to the west on Sunday and Monday, and a more active pattern
develops over the High Plains with continued precipitation chances
as disturbances move through the flow.
Heat: Hot temperatures are expected on Wednesday and Thursday
before a cooling trend in the extended. Highs top out in the upper
90s along and west of the Colorado border while temperatures in
the 100-104 range are forecast to the east. With heat index values
near 105 along and east of Highway 25, am thinking a heat advisory
may be needed for at least Wednesday and Thursday.
Temperatures look to trend downward from Friday onward with highs in
the upper 80s to low 90s by Sunday. Lows will be in the 60s to mid
70s in the long term period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1128 AM MDT Mon Jul 18 2016
Stratus/fog has cleared at both terminals and VFR conditions should
prevail at KGLD and KMCK through the TAF period. Winds will shift
from the northeast to the southeast, then to the south as a warm
front lifts over the region. Thunderstorms are expected to develop
and spread northeast this afternoon and overnight tonight. A few
storms are possible at KGLD, however confidence was too low to
include mention. Better chances will be at KMCK late this evening
and early Tuesday morning. VCTS group was included at KMCK during
period highlighted by majority of guidance. Developing LLJ will
result in a period of low level wind shear after 06Z through
sunrise.
&&
.GLD Watches/Warnings/Advisories...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1229 PM CDT MON JUL 18 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 313 AM CDT MON JUL 18 2016
An MCS moving through northwest MO has formed an outflow that is
currently pushing southwestward towards far northeast KS. A west to
southwesterly low level jet is intersecting this outflow, and is
responsible for additional storm development in that area. Those
storms may backbuild into far northeast KS in the next few hours
until the cold pool quits progressing or mixes out. There is also
increasing isentropic lift taking place in central KS. Storms have
formed along this axis of lift that stretches back into southwest
KS. The NAM shows this isentropic lift on the 310 K surface nosing
into northeast KS in the next few hours with the coverage most
likely staying isolated to scattered. Therefore have kept slight
chances across the northwest portions of the forecast area through
just after sunrise. How far east these showers and storms extend is
uncertain at this time. Several consecutive runs of the HRRR have
shown this activity reaching east central KS before it weakens as
the low level jet decreases. Given the HRRR is already off on storm
location means perhaps it might not get far into the forecast area
all together. Soundings show about 1500-2000 j/kg of mucape above
drier air in the lower levels and a weak nocturnal inversion. The
effective shear is also around 30 kt, which is marginal from
organization. If a storm were to realize this instability perhaps a
strong localized wind gust could not be ruled out within the
stronger cells.
Later today the temperatures will warm again into the mid 90s to
lower 100s with dew points in the upper 60s to lower 70s. This
combination will cause heat indices between 100-105 this
afternoon, and a heat advisory is in effect.
.LONG TERM...(Tuesday through Sunday)
Issued at 313 AM CDT MON JUL 18 2016
Heat indicies continue their climb through the week, with Tuesday
bringing another day in the 100-105 range, followed by a jump into
the 103-109 range by Wednesday and continuing in that range into
Friday. As a result, and in collaboration with neighbor offices,
have opted to carry a heat advisory through the week. With several
days of heat indicies above 100 by mid week, may need to upgrade
to a warning for the mid to late week time period, considering the
cumulative impacts of several days of heat. In short, outdoor
activities this week will require vigilance about the potential
impacts of several days of heat advisories. Please plan
accordingly.
EC and GFS both try to break down the ridge through the weekend as
an upper trof progresses across the US/Canadian border and sends a
front southward in its wake. EC is stronger and farther southward
with the upper trof, and therefore faster moving the boundary
into southern Kansas by late Saturday. The GFS has a slower
progression but does bring the front through on Sunday. Sensible
weather impacts would be an increasing chance for rain into
Sunday, and a break from the heat of the week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1227 PM CDT MON JUL 18 2016
For the 18Z TAFs, expect VFR conditions to prevail throughout the
period. Winds should slowly veer to a more SSE component into the
afternoon and evening. Slightly stronger winds near KMHK until
around the 01Z time frame.
&&
.TOP Watches/Warnings/Advisories...
Heat Advisory until 7 PM CDT Friday for KSZ008>012-020>024-026-
034>040-054>056-058-059.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...Drake