Scientific Forecaster Discussion
fxus65 kabq 292331 aaa
Area forecast discussion...updated
National Weather Service Albuquerque nm
531 PM MDT Mon may 29 2017
00z taf cycle
band of convection shifting east-southeast and weakening as it does
so. Expecting this trend to continue during the next couple of hours.
Isold showers and storms may linger until 04z or so. Models hinting
at possibility at patchy MVFR cigs across the eastern plains
overnight into Tuesday morning. Scattered convection forecast once
again Tuesday afternoon and evening with the exception of the
northwest quarter where drier air will win out. A few of the
stronger storms along and east of the Central Mountain chain could
produce isold MVFR cigs and vsbys along with small hail.
Previous discussion...250 PM MDT Mon may 29 2017...
atmospheric moisture will continue to increase over the state
through Wednesday, resulting in increasing chances for showers and
storms. Storms will be moving slowly on Tuesday and Wednesday, so
rain amounts will likely increase. Daytime temperatures will trend
down through mid week and generally be below normal, especially
across the southeast plains on Wednesday where highs are forecast to
be 15 to 20 degrees below normal thanks to clouds and rain cooling.
A warming trend will begin Thursday and continue into Saturday, with
temperatures reaching back to near normal areawide. Drying from the
west on Thursday and Friday will limit chances for storms to the
northeast and far southeast, but chances for storms will trend back
up and spread west to around the Central Mountain chain over the
weekend thanks to a backdoor front.
pwats are trending up, with the 12z kabq upper air sounding showing
0.53" compared to yesterday's 0.36". 24hr surface dewpoint change
values are an average +5 degrees across central and eastern New
Mexico, reflecting increasing moisture over the area. This increase
in moisture combined with daytime heating has resulted in a more
robust round of storms this afternoon, with a few strong storms
possible. A relatively dry lower boundary layer, weaker jet dynamics
and limited surface based instability are resulting in garden
variety high-based storms with a few stronger cells capable of
producing hail up to one inch in diameter and wind gusts approaching
60 mph. One or two pulse-type severe storms are not out of the
question this afternoon and early evening.
Atmospheric moisture will continue to trend up through Wednesday,
although winds aloft will be on the downtrend resulting in less shear
and slower storm motion. This means any severe threat should trend
down while the threat for locally heavy rainfall trends up. The 12z
NAM continues to be much more bullish with the quantitative precipitation forecast for Wednesday
compared to the GFS, with +1" amounts possible. Higher quantitative precipitation forecast amounts
makes more sense given very slow storm motion and a well above normal
precipitable water atmosphere. The 12z NAM and GFS continue to show the precipitable water at
kabq ramping up to near 0.90" on Wednesday, which would beat the
daily record value of 0.83". Wednesday still looks like the coolest
day this forecast cycle, with highs up to 20 degrees below normal
across the southeast plains.
A drying/warming trend is forecast to begin Thursday, but differences
between the 12z GFS and European model (ecmwf) with the approaching upper level trough
is leading to lower forecaster confidence in the timing and magnitude
of that trend. It does appear that chances for storms will be
confined to the eastern plains and northern mountains by Friday and
then back westward to the Central Mountain chain over the weekend
thanks to a backdoor front.
showers and thunderstorms erupted late this morning over the high
terrain and continue to increase in coverage this afternoon. Storms
will continue to move toward the east or southeast through the
evening and may grow into a cluster across NE and ec nm. Thus,
several areas should see wetting rains east of the Central Mountain
chain. Some storms will contain heavy rain and small hail as well as
gusty winds. Meanwhile, from the Rio Grande Valley westward, a mix
of wet and dry storms remain the rule and gusty winds will continue
to be the main threat with these storms.
Though the moisture return will get disrupted by the storms this
evening, once storms dissipate, the return flow will make another
appearance, and moisture values will continue to increase. This
will set the stage for another active day Tuesday, though storms
should be mostly of the wet variety, except near The Four Corners.
Storms should form along the high terrain and shift toward the east
or northeast. A weak disturbance aloft propagating across southern
nm should help generate storms across the plains, particularly the
southeast plains, Tuesday night into early Wednesday.
Wednesday should be the most active day of the week as the
aforementioned disturbance remains over the southeast nm plains and
moisture continues to be drawn in from the Gulf. Widespread storms
with wetting rains are expected. Storm motion will change more
drastically on Wednesday afternoon. Storms should move toward the
north or northwest for most areas, though slowly. By Thursday, the
disturbance will shift eastward and drier air will begin to filter
into at least western nm. This will shift the focus for convection
across the east. By Friday, drier air will continue to push in from
west to east, limiting precipitation chances further. Though small
chances will persist east of the Central Mountain chain.
Temperatures will remain below normal throughout much of the week,
with the coolest day being Wednesday thanks to the widespread cloud
cover and precip. Temps will warm back up Thursday and continue on
Friday. Most areas on Friday will be with a degree or two of normal.
Another moist back door front, or perhaps two, will arrive over the
weekend, which may increase storm chances again, at least for areas
along and east of the Central Mountain chain.
Only ventilation concerns are on Tuesday and Wednesday where spotty
poor vent rates exists across portions of north central and central