Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Albuquerque nm
1148 PM MDT Sat Apr 25 2015
06z taf cycle
still some virga showers persisting across the northern mountains...but
the next wave of precipitation has moved into western nm...impacting kfmn
and kgup. Precipitation will expand eastward early Sunday morning...
impacting central nm by or shortly after sunrise and over eastern
nm by the way 18 and 21z. Several hours of rain is likely at most
locales...but duration may be a bit overdone in tafs. Later
issuances will likely trim back rainfall duration as confidence in
timing increases. Ts will be possible just about anywhere...but best
chances are across NE nm. MVFR ceilings will be possible with any
precipitation...and mountain obscurations are likely. Visibilities may be lowered in
heavier precipitation. Though rain will be dominant...some high Elevation
Mountain snow will be possible across the north central mountains west to
northwest winds will also increase Sunday afternoon...with breezy to windy
conditions likely. The strongest winds will from ksrr to krow
where gusts near 35kt are possible. NE nm will be the exception to
the west to northwest winds due to a back door cold front edging into the
area in the afternoon. This front will sink southward after 00z Monday as
widespread precipitation develops behind it.
Previous discussion...528 PM MDT Sat Apr 25 2015...
updated probability of precipitation for tonight based on observation and latest guidance. Also
added the southern sangre Delaware cristo mts to the Winter Storm
Watch...as they were unintentionally omitted. Updated zone forecast product and west-southwest
Previous discussion...336 PM MDT Sat Apr 25 2015...
significant wetting event upcoming for the Sunday to Monday period
as potent trough aloft dives into Arizona tonight and morphs on its
south end into a closed low early Sunday. Strong upward vertical
velocity ahead and with this system plus the Pacific moisture the
system is dragging along will give most locales at least light to
moderate rain amounts. By far the heaviest precipitation is
expected to fall across the sangre Delaware cristos east across the far
northeast plains. Heavy snow accumulations are pretty likely in
the former and to a somewhat lesser degree across western portions
of the northeast Highlands and vicnity of Raton Pass and more
generally the higher terrain near the Colorado line. Drying and
warming from Tuesday on with maybe isolated mountain convection.
significant precipitation event upcoming for sun to Monday period as a
strong upper trough dives into Arizona tonight and strengthens into a
closed low on its south end early Sunday. Strong forcing ahead
and with this system plus Pacific moisture the system brings with
itself will give most locales at least light to moderate rain
amounts. Heaviest precipitation by far is expected across the sangre Delaware
cristos east across the far northeast plains. Heavy snow
accumulations are pretty likely in the former and to a somewhat
lesser degree across western portions of the northeast Highlands
and vicnity of Raton Pass and more generally the higher terrain
near the Colorado line. Will be continuing the Winter Storm Watch
for the same areas as previously issued. Biggest forecast challenge
seems to be how far...if at all...the accumulating snow will
develop into the lower terrain of the NE Highlands and the Raton
ridge/Johnson Mesa area. While thickness values and 700 mb temperatures
look ever so slightly lower for this area than was depicted 24
hours ago...still are facing the fact that much of the wraparound
moisture on north to northwest side of low will have at least some Gulf of
Mexico origin and other consideration is that air mass north of
the back door front is not very chilly. Drying and warming from
Tuesday on with maybe isolated mountain convection.
Jet streak on the northwest to west side of upper low will combine with
residual low level moisture to produce at least a few showers and
thunderstorms over the western and northern mountains Tuesday afternoon and early
evening. Healthy upper level ridge begins to translate east toward
then over nm Wednesday and Thursday...warming temperatures to above seasonal
norms limiting convection chances to slight...mainly over the northern
mountains. Ridge axis slides east of nm Thursday night and Friday. GFS
and European model (ecmwf) in good agreement that a relatively moist south to southwesterly
flow aloft will develop Friday into early next weekend...resulting
in isolated to perhaps at times scattered showers and storms.
what a difference a year makes. Cool and relatively moist conditions
continue to favor the region today ahead of the next weather maker
for Sunday and Monday. This next system will be the type to mitigate
fire weather concerns for several days if not weeks in some areas.
But first...the marginal critical conditions developing today over
the east Central Plains and parts of The Highlands will continue
through sunset. Humidity will then trend up tonight as deep moisture
advection increases from the west. Wetting rainfall is expected to
begin west of The Divide before midnight then shift east into the
Rio Grande Valley around sunrise. The center of the upper low will
slide east along the I-40 corridor through Monday and deliver a
significant soaking rain event for much of the area...especially the
northern mts and the northeast plains. Temperatures will become cold enough
for heavy snow accums above 8000 feet Sunday night and Monday morning
where up to 1 foot is possible. It will likely snow in lower terrain
areas but with limited accums. The other good news is temperatures remain
15 to 25f below normal Monday and Tuesday before rebounding back
toward normal Wednesday. This will allow snow to melt slowly and
soil moisture values to stay elevated for several days afterward in
the lower elevations.
A ridge will slide into the area Wednesday then crest Thursday before
breaking down Friday. Vent rates will deteriorate with perhaps some
poor values Thursday. Relative humidity recoveries will be high for most areas with
wet soils and nocturnal inversions in place. Guidance indicates a
good deal of middle level moisture trapped beneath the ridge which will
enhance the recycling of rain showers and keep cloud cover around for
late in the afternoon.
Chances for more wetting rainfall increase by the weekend as a low
pressure system develops very slowly along the California coastline.
This will help force a monsoon-like pattern with moist and unstable
south southwest flow over nm. Daily rounds of showers and storms are
possible Friday through next Monday. A quick glimpse at the longer
range pattern through the first few days of may indicates elevated
moisture and below noral temperatures continuing.
Winter Storm Watch from Sunday evening through Monday afternoon for
the following zones...nmz513>515-527.