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Area forecast discussion...updated 
National Weather Service Albuquerque nm
1130 PM MDT Thursday Apr 17 2014

Aviation...
06z taf cycle
areas of low ceilings will develop across the southeast plains early Friday
morning. A few hours of MVFR conditions will impact krow and east to
nm/Texas border with very low confidence that clouds will push farther
north. Breezy Gap winds will diminish within the next 5 to 6 hours
at kabq and ksaf. An upper level storm system will advect middle and
high level clouds across area through Friday evening. Isolated dry
thunderstorms will form over the western and northern high terrain Friday
afternoon...but not expecting any storms to impact terminal
sites. Southerly to southeasterly winds will strengthen through
Friday afternoon areawide with slight decreases after sunset.

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Previous discussion...301 PM MDT Thursday Apr 17 2014...
synopsis...
an upper level trough crossing from the west will bring
precipitation mainly in the form of showers and thunderstorms
Friday through Saturday night. Models now depict a secondary
trough dropping southeastward across the area Sunday. A back door
cold front will then sag into northeast New Mexico Sunday night
into Monday keeping showers and thunderstorms in the forecast for
the northern mountains and northeast plains through Monday
evening. Strong southwest winds are expected Tuesday and
especially Wednesday as a large upper level low pressure system
passes north of New Mexico steering the jet stream overhead. Low
humidities will accompany the strong winds Tuesday and Wednesday
leading to fire weather concerns.

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Discussion...
an upper level low pressure system approaching San Diego from the
west should weaken and lift east northeastward across New Mexico
as an open wave Friday through Saturday night. Ahead of the system
a southeasterly low level return flow is expected to advect
better low level moisture into central and especially eastern
parts of the forecast area tonight into Friday. Showers and
thunderstorms will break out starting Friday as a preceding short
wave crosses northern and central nm from the southwest.
However...many of fridays storms will be dry west of the Central
Mountain chain. Precipitation will then become wetter and more
widespread Friday night through Saturday...before decreasing in
coverage and intensity Saturday night as the base of the upper
trough crosses.

Sunday should see light precipitation chances become
more widespread again as a secondary trough sags southeastward
over the area. This perturbation is prognosticated to nudge a back door
cold front southward into northeast nm...which should keep the
northern mountains and NE plains convectively active through
Monday evening despite a ridge of high pressure crossing aloft.
Temperatures at 700 mb are expected to remain above freezing as
the weekend weather systems cross...so any snow accumulation
should be limited and favor only the highest mountain peaks.

After thick cloud cover and fairly widespread precipitation drop
temperatures a few degrees across much of the forecast area on
Saturday...readings should gradually trend upward Sunday through
Tuesday. Southwest winds should also begin to gust in the 35 to 50
miles per hour range Tuesday as the jet stream approaches the state from the
northwest and a Lee trough develops at the surface. Winds will strengthen
farther Wednesday as the jet stream shifts more directly overhead
and the Lee trough continues to deepen. Fire weather concerns
should abound both Tuesday and Wednesday due to the strong winds
and accompanying low humidities.

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Fire weather...
growing confidence for a multi day significant strong wind/low
humidity period Tuesday through Thursday of next week. Peak day in
terms of low humidity and wind appears to be Wednesday. The
atmosphere should also be unstable with near to above normal temperatures
and Haines 5 to 6 values most areas. Will be monitoring cloud cover
trends as we get closer to the event period the most unstable day
appears to be Tuesday. Increased moisture and thunderstorm chances
occur Friday and peak Saturday. Drier storms on Friday into Friday
evening with strong downburst wind potential.

As far as the rest of today...skies will continue to clear as a weak
middle level dry intrusion moves in from the west. Surface dewpoints
will remain on the higher side as southeast return flow increases
this evening and during the overnight. Looking for some modest gap
winds along the central mountains as a result. Relative humidity recoveries will be
good to excellent across the eastern half. Less so near the Arizona
border.

As mentioned above...moisture will flow up from Mexico and the Gulf
starting Friday. This is in response to a weak wave currently found
off the southern coast of California. As the wave draws closer to
the forecast area...the atmosphere will destabilize and initiate
shower and thunderstorm development. The activity will be on the
drier side across western and central areas...especially west on
Friday and most likely linger into Saturday evening. Abundant
dewpoints that currently reside over southern Texas...50s...will
eventually make there way up into eastern portions of the forecast
area. This moisture will feed the wetter variety of storms Friday
night into Saturday. Models vary a little bit on wetting
precipitation potential across the west...especially northwest on
Saturday but figure localized wetting rain would occur.
Otherwise...some wetting rain remain possible across the east. The
wave is still on track to cross over the area Saturday night with some
residual impacts Sunday. Mainly in the form of isolated to widely
scattered instability showers favoring the north. The strongest
winds would be associated with downdrafts from showers/storms during
this period although strengthening southerly wind ahead of the wave
on Friday will provide some breezes to the area. Some occasionally
breezy west/northwest winds would be found on the backside of the
departing low but shouldnt be as strong compared to Friday. Friday
looks to be a dynamic day although not a classic dry lightning fire
event due to the lack of preceding heat/dryness. Using lal 6 for a
couple of zones across the west. Humidity values would be marginally
low across the western/central areas on Friday but be unseasonably
high areawide Saturday.

Models still show ridging with a slight warmup/drying trend on
Monday. Wind doesnt look to be much of a factor due to lighter winds
aloft. Cant rule out some shower activity across the northeast third
to half. Models have been showing that the past few runs.

All eyes still remain on Tuesday through Thursday. Models have been
showing a wind event scenario the past several runs. GFS and
European model (ecmwf) have also come more in line in terms of how deep the trough
would get Wednesday night/Thursday. The consensus is that this would
be a classic dry Pacific trough passage. Mainly a wind bag with an
accompanying dynamic dry slot and Post dry intrusion. There is a
signature for a tightening dry line across the eastern plains Monday
night into Tuesday as the trough approaches. Thus marginally low
humidity values depicted in the gridded forecast across the east
Tuesday afternoon. Much lower across western/central areas. Relative humidity
values will fall across that area on Wednesday as the flow takes on
a more westerly tilt to it although temperatures cool to near normal
readings across the far west. Should be plenty of instability with
this system passage although cooling will take over later Wednesday
west and pretty much areawide Thursday. Confidence continues to grow
and thinking pretty good at this point.

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Abq watches/warnings/advisories...
none.

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