Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Albuquerque nm
1214 PM MDT Tuesday Jul 22 2014
18z taf cycle
the center of the middle level high pressure system will drift
northward over Colorado today allowing better moisture into nm from the
east and southeast. Therefore...expect increased coverage of rain showers/thunderstorms and rain with
models favoring the central Montana chain and east plains. Storms will
generally move toward the west and northwest causing cells that form over
the mts to cross adjacent lowlands like ksaf...kabq and kgup.
There is some uncertainty on the timing of storms at taf
sites...and locations along the east slopes of the central Montana chain
could be hit by multiple storms through the afternoon and evening.
Erratic microburst wind gusts to 50 miles per hour will be possible with
mainly wet microbursts in the east and a mixture of wet/dry
microbursts in the west. Ts outflow will likely produce gusty East
Canyon winds in the Rio Grande Valley late this afternoon into the
evening. Much of the convection should be finished by midnight
with SW and S central areas favored for isolated late night storms.
Previous discussion...334 am MDT Tuesday Jul 22 2014...
the upper high center will transition to over southern Colorado
today...allowing rich atmospheric moisture to move west across
central and western New Mexico. This will lead to an uptick in
thunderstorm activity from the Central Mountain chain westward...
especially during the evening and overnight hours. Storms will be
moving slow with the potential to produce heavy rainfall and
localized flooding. Above normal temperatures will continue into
the weekend with the dominant upper high parked over the region.
Thunderstorm activity will decrease late in the work week going
into Saturday...then increase late in the weekend and early next
week as the upper high slides off to the west and allows a
backdoor front to usher moisture westward across northern and
central New Mexico.
despite a dominant and anomalously strong upper high over the
area...we're forecasting an uptick in thunderstorm activity today
and tonight. The upper high is forecast to strengthen to near
600dam at 500mb and become centered over southern Colorado
today...allowing moisture to advect west into central and western
portions of the forecast area under the upper high circulation.
Both the latest NAM and GFS show precipitable waters at kabq increasing to
between 1.1-1.2 inches by midnight...which would be well above
normal for middle to late July. Plenty of surface heating is forecast
today ahead of the moisture surge...so instability will be
sufficient to keep convection going well into the overnight
hours...especially west of the Central Mountain chain. Storm
motion will be 5 to 10 miles per hour (at best) to the west-northwest...but storms will
likely propagate on outflows. Due to slow storm motion and the
higher pwa arrive Sunday night. With the
moisture and increased rain chances...look for high temperatures
to trend back down closer to normal.
high pressure is expected to center just north of New Mexico today
with moisture increasing in the eastern half of the state through
the afternoon and eventually into the Rio Grande Valley and toward
the Continental Divide this evening. This will once again leave the
northwest plateau as the driest section of the forecast area where
minimum relative humidity will fall to 10-15 percent. Storms will be quite active
near and just east of the Central Mountain chain this
afternoon...transitioning farther west this evening. Synoptic
scale winds will be fairly light...but thunderstorms will be capable
of hurling out some locally erratic and strong outflow gusts...some
of which may even spill through the gaps/canyons of the Central
Mountain chain for a brief time.
Into Wednesday the focus for storms will continue to shift environment...locally heavy rainfall is possible with
potential for localized flooding (especially on burn scars).
Just as fast as precipitable waters increase to above normal...they are forecast
to decrease to well below normal Wednesday night into Thursday (at
least here in abq) due to drying as the upper high forecast moves
back south over New Mexico. Western areas will be favored for
thunderstorms on Wednesday...with moisture moving around the upper
high circulation on Thursday and favoring the northern mountains.
Friday looks to be the hottest day this week with the lowest probability of precipitation...
favoring the northern mountains and northeast.
Changes come by late in the weekend and especially next week as
the upper high is forecast to gradually move west to over Arizona and a
high amplitude upper level trough carves out over the eastern U.S.
This pattern will allow for backdoor fronts to move SW across the
forecast area and replenish moisture for renewed thunderstorm
activity. The first push looks tot farther
west as the moisture migrates toward the Arizona border. This will give
the northwest plateau a reprieve from the very low afternoon relative humidity
observed the past few days while storms decrease in coverage in the
eastern plains. Storms will follow the moisture as it orbits around
the center of high pressure that will establish itself more directly
over nm by Thursday. Thus...Thursday and Friday the northern zones
are expected to be favored for storms...but overall temperatures
will be warmer than average across the forecast area. The north
central to northeast will then become favored for storms into the
weekend as a couple of back door fronts arrive...with the second one
on Sunday evening providing a better focus for more precipitation.