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Area forecast discussion...updated 
National Weather Service Albuquerque nm
602 am MDT Wednesday Aug 24 2016

12z taf cycle
shortwave trough will be overhead tdy. The atmosphere will
destabilize fairly quickly as a result of this trough and lead to
increased sh/ts impacts at central terminal sites. Went a bit
bullish for thunderstorms in the vicinity at aeg/abq/saf/lvs due to the trough position.
Bracketed the thunderstorms in the vicinity with vcsh. Later shifts can add tempo and
concentrate on actual impacts including wind. Some preliminary sh
impacts possible during the morning hrs at gup/fmn. Main back door
cold front will push into eastern areas during the overnight hrs
and will tend to focus sh/ts across NE and ec areas. Tcc and to a
lesser extent lvs should be impacted. Used vcsh at tcc to capture
that impact. Could see that terminal forecast see some changes as
we get closer to the impact period. Models not bullish for low
cigs at this time due to the cold front tonight. Will be watching
lvs/tcc closely.



Previous discussion...352 am MDT Wednesday Aug 24 2016...
fairly robust low pressure trough aloft to slowly cross the north
half of the state today and will interact with enough moisture to
produce scattered to, at times, numerous showers and
thunderstorms from later this morning through the early evening
hours. A few strong storms are possible along with some locally
heavy rain, especially from the northern mountains eastward.
Farther south the atmosphere will be drier and so significantly
less activity is expected. The previously advertised back door
cold front that was to come through most of the state between late
today and Thursday now looks weaker and later to arrive, so
western areas of the state may not see as much, though still some,
shower and storm activity for Thursday into the weekend, while the
east fares pretty well.


models have been Flipping back and forth somewhat with regards to
the strength of the slow-moving mid and upper level trough across
the state today into tonight. The 00z models were generally at
least a little less bullish with the amount of convection across
central nm today, likely due to trough passage being just faster
enough to kick its axis just east of this area close to peak
heating period. North central and NE nm still look very much
favored for the most widespread and heaviest showers and storms.
Very quick look at the very latest, 06z, run of the NAM model
indicated a sharper and slightly slower moving trough extending a
little farther south across nm as it slowly comes by and thus that
latest run shows more convection/quantitative precipitation forecast across central nm and, if
anything is even wetter for the NE. Decided to beef up N central
and NE nm thunderstorm wording by adding gusty winds, small hail
and locally heavy rain wording for this aftn. That could carry
over for a few hours into the eve for the NE, but will defer to
day crew to consider adding for that time period based on aftn
trends and 12z model run data. Would not rule out a very few
severe storms for roughly the NE third of the state, but
confidence only high enough as of this writing to go for the
'strong' storm indicators.

Overall the last 2, at least, model runs are later and a little
weaker with the passage of the upcoming back door front into and
across much of the fcst area. This does not Bode well for as
strong a wetting rain coverage uptick across the west third to
perhaps half of the state for much if not all of period from Thu
into the weekend. While there still is some moistening of the
atmosphere for this part of the state, the low levels may not see
as much of it, so decided to ease back pops slightly to moderately
for the west Thu and to a bit lesser degree Fri and Sat.

Also, the previously much heralded drying trend for Mon and Tue is
being delayed by both the GFS and European model (ecmwf) models, at least for east
and much of central nm. But west central and NW locales are still
largely dried out. Since this is a new trend and still a ways out
in time, decided to lay off significant changes for now for that



Fire weather...
a moderate change made to the inherited weather grid package near
term with the delay in the back door cold front influencing
dewpoints/humidity values across central areas of the forecast area
Wed night. Still looking at a moisture seepage from the east but
doesnt appear to be as prolific as earlier thought. However...beefed
up gaps winds Thu night along the central mtns and this will result
in a little stronger moisture seepage from the east. Next weeks
drying trend also looks to be a bit more tempered as the mid and
long range models have delayed the onset of the building high over
nm. Keeping the initial high center further to the west like they
were depicting a couple of days ago.

Shortwave trough will be found over the central/southern rockies
today. Storms will fire up fairly quickly today due to the
instability associated with the trough and initially favor central
areas. Latest models are coming in a bit stronger for precipitation
chances and wetting rain potential that earlier models for central
areas today. This jives with current satellite imagery. An initial
northerly wind shift and a deeper back door cold front will push
southward across the eastern plains today/tonight. Convergence
associated with the front combined with the trough passage will lead
to widespread wetting rain across at least the NE third. The trough
should exit to the east by early thur morning and leave a drier
subsident pattern behind it. As mentioned above, the front should
eventually seep into portions of the Rio Grande Valley late Wed
night. If significant convection associated with the trough/front
ends up moving further south than what the models are showing...then
the moisture push westward will be more pronounced.

Short term models remain steadfast with a shortwave ridge developing
over the area Thursday as the trough is east of the state. Slight
differences between the NAM/GFS in terms of shortwave presence over
the eastern plains...otherwise the pattern from both models look
similar. Residual...low and mid level moisture should result in
scattered thunderstorms favoring the mountains. Storm movement would
tend to be light except for the far north thus increasing wetting
rain potential within the mountains.

The area would be caught in moisture recycle model Friday with
lasting effects into the weekend. It is possible that some monsoonal
moisture could seep northward out of Mexico during the weekend
period. The NAM/GFS and lesser extent European model (ecmwf) are showing some sort of
weak troughing to the west of nm. If this were to occur...then
moisture should flow northward ahead of the weak trough and create
less penetration of the drier air from the Great Basin. Will be
monitoring that trend in the modeling. Either way...scattered
thunderstorms would tend to favor the Continental Divide to central
mtn chain.

As mentioned earlier...long range models are depicting less drying
across the forecast area for next week. This will largely be
dependent on the subtropical high location and impending Pacific
trough. Both the European model (ecmwf)/GFS are depicting a deepening pac trough over
the western tier of the US while eventually nudging the upper high
further east. Models the past few days have had a hard time
resolving the trough/ridge interaction as well as timing. Gut
feeling suggests models will become more moist for next
week...especially as the Pacific trough deepens over the western
tier of the US. Confidence at this time is low to moderate until
consistency can develop within the run to run modeling.

Ventilation rates will be pretty decent today but lower considerably
on thur thanks to lower transport winds. Some improvement is
expected on Fri even though mixing heights lower. Mixing heights
will rise some during the weekend although transport wind trends
will be variable thus leading to variable vent rates.



Abq watches/warnings/advisories...



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