Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Albuquerque nm
556 PM MDT Friday Sep 4 2015
00z taf cycle
southwest winds aloft continuing to transport deep subtropical moisture
associated with Tropical Storm Kevin over nm. Areas of light showers
will continue overnight with a thunderstorm or two possible over
northwestern nm including kgup and kfmn through 05z. Mts occasionally
obscured in clouds and light precipitation. Thunderstorms will produce wind gusts
to around 40kt. Areas of MVFR/IFR ceilings and visibilities possible after 06z
as temperatures drop to near dewpoint temperatures.
Previous discussion...310 PM MDT Friday Sep 4 2015...
abundant moisture will continue to flow northward ahead of a
Pacific trough through Saturday. This means scattered to numerous
showers and thunderstorms favoring the western two thirds. Heavy
rain will be possible at times especially along and to the west of
the Continental Divide. The Pacific trough will push eastward and
drag drier air into northern/central New Mexico starting on
Sunday with continued impacts into early next week. Showers and
thunderstorms will become less during this period but wont totally
go away. A series of back door cold fronts are expected to impact
central/eastern areas middle to late next week. Storm coverage should
increase as a result of the frontal pushes.
water vapor and infrared satellite imagery continue to show a deep tap
of middle/upper level moisture originating from the subtropics as
well as ts Kevin. Higher surface dewpoints have also caught up
with the abundant upper level moisture. The main bubbling
convection based on the latest visible satellite imagery and lightning
data is pronounced across the western third. Decided to beef up
probability of precipitation a bit more for this area going into the evening/overnight
hours. Some areas should received on and off rainfall the entire
night based on precipitable water values/upslope saturation. Cant see a distinct
vortice wave within the WV imagery although a strong sub tropical
jet for this time of year will edge closer to the area.
It appears that the last big hoorah in terms of widespread
precipitation/heavier rain is Saturday. Bumped up probability of precipitation a bit more
for areas on Saturday although cloud cover could be a concern for
some of the period. The Pacific trough and corresponding sub
tropical jet will have moved a bit closer to the area which will
help aid upper level destabilization. High level precipitable water values of
1.5 to 2.5 Standard deviations will remain over the area although
lessen slightly from the peak values Sat morning. Also lowered
high temperatures slightly below model guidance to account for abundant
cloud cover across western/central areas. Similar to what occurred
Models remain in agreement with much less convection or
thunderstorm coverage starting on Sunday. The Pacific trough will
shift eastward and drag drier air from the west-northwest. Temperatures will rebound
due to less cloud cover potential.
The center of the high should remain south of the state early next
week. A diffuse or weakened moisture plume should develop around
the upper high and allow thunderstorm coverage to gradually
increase although they would favor the mountains it appears that the
initial frontal push that was projected on Monday/Monday night
across the east looks to be more Tuesday/Tuesday night. That push looks
to be weak. A more robust moisture push via the back door cold
front should occur later in the week although timing/strength is
in question due to run to run model inconsistencies.
south to southwest winds aloft in advance of upper trough to our
northwest have continued to pull deep moisture into New Mexico.
Morning soundings indicated a stabilizing inversion under the core of
the plume...with better instability along the periphery of the
plume. This seems to be panning out as a large area of mainly light
showers tracks northeast over central nm this afternoon while a few
lightning strikes noted over far northwest nm.
Models still tend to shift the Theta-E ridge axis to the east
Saturday...with potential for storms with heavy rain stretching from
the west central mts to the rgv and sangre Delaware cristo mts. Storm
motion will continue to be to the northeast at around 20 to 30 miles per hour.
Therefore the northeast/east Central Plains may begin to see better
chances of wetting rain Saturday into Saturday night.
Drier air remains forecast to overspread the northwest and north
central Sunday and the upper trough passes to our north...but the
plume is not as suppressed as far south Sunday into Monday as was
suggested 24 hours ago. That said...the northwest and north central
will see none to minimal probability of precipitation during this time as dew points crater.
Highs Saturday through Monday will remain near to below average
central and west...and near to above average east...but with a slow
More moisture may linger into the middle of next week...with the GFS
now building the upper ridge more strongly and weakening the
westerlies across the northern rockies than it did yesterday. There is
still a front next Wednesday that reinforces low level moisture in
the east and central...and yet another next Saturday. Some of the
moisture may mix out especially in the west during the day...and
with the ridge axis to our west...the best chances for convection
with wetting rain will be from the central Montana chain eastward. High
temperatures will be within a few degrees of average...and overnight
recoveries will be good to excellent for most areas...except the far
northwest late next week where recoveries may be fair or even poor.
Vent rates forecast to be mostly good to excellent Saturday...
become mostly good Sunday...but increase again Monday. Tuesday will
see a downturn...with areas of fair to poor west and north...but
improvement forecast Wednesday.