Flash Flooding in New Mexico, July 1, 2022

Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
1131 AM MDT Fri Jul 1 2022

.AVIATION...
18Z TAF CYCLE
VFR conditions prevail and are forecast to persist outside of
scattered/numerous storms this afternoon/evening, where MVFR
conditions are likely. Short-lived IFR conditions can not be ruled
out with the stronger storms. Thunderstorm impacts are unlikely at
KTCC and KROW and most likely at KLVS and KGUP, followed by KSAF and
KAEG.

11

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.PREV DISCUSSION...951 AM MDT Fri Jul 1 2022...
.UPDATE...
Updated forecast to include the southwest mountains and the San
Agustin Plains and adjacent lowlands in a Flash Flood Watch for this
afternoon/evening due to slow storm motion, above normal PWATs,
modeled qpf and burn scar considerations. Otherwise, forecast on
track.

11

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.PREV DISCUSSION...241 AM MDT Fri Jul 1 2022...
.SYNOPSIS...
Beginning today and into the holiday weekend, high pressure in the
upper levels of the atmosphere will shift east of New Mexico. As a
result, monsoon moisture will increase over New Mexico with higher
chances for showers and thunderstorms through early next week. The
highest chances for rain and thunderstorms will stretch from the
southwest mountains into the northern mountains and northeast
highlands with scattered activity filling in between each day.
Locally heavy rainfall will be possible each day, and this could lead
to excessive runoff or even flash flooding for some steep terrain and
other vulnerable areas. Temperatures will remain slightly below
average in western New Mexico while eastern areas remain closer to
normal.

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.DISCUSSION...
SHORT TERM...(TODAY THROUGH SATURDAY)...
Water vapor imagery shows the monsoon plume situated more directly
over western and central NM this morning, allowing for an expected
rise in PWATs to ~1.00" today and above 1.00" this weekend.
Meanwhile, a convective outflow boundary has pushed southward into
east-central NM. This will be an interesting feature to watch
regarding afternoon storm activity today. The NAM12 and HiRES-ARW in
particular are picking up on the higher Td's in the mid-upper 50s,
generating greater instability later today highlighted by SBCAPE
800- 1200 J/kg. However, other model solutions show lower
instability, but are initializing with slightly lower Td's closer to
50 this morning. Thus, these solutions are showing weaker storms
rolling off the Sangre de Cristo's over the northeastern plains. Have
hedged the forecast toward the higher instability solution given the
higher Td's being observed behind the front and at Clayton so far.
Regardless, these storms forming off the Sangre de Cristo Mountains
will be under the influence of stronger steering flow pushing them
eastward over Colfax, Harding, and Union Counties late today and
evening. The question is how heavy the rainfall will be with these
storms.

Meanwhile, typical afternoon convection is expected to initiate over
the high terrain of western and northern NM near the noon hour.
Weaker steering flow will allow for slower and more erratic storm
motions, with activity spreading to nearby valley locations late in
the day and through the evening. Given the higher atmospheric
moisture, greater storm coverage, and slower storm motions, will
continue the Flood Watch for the Cerro Pelado, Cooks Peak and HPCC
burn scars. There is a small expansion to include the Northeast
Highlands for drainages from the HPCC burn scar that empty into this
zone near Las Vegas. Friday's convection will slowly taper off
through the evening. Saturday will see a rinse off and repeat
forecast as the monsoon plume holds steady over NM. A centroid of the
upper high looks to be over southeastern NM Saturday with an
easterly wave over the TX Big Bend area. This will keep storm
activity focused over the western and northern high terrain. Storm
motions will be weakest over the Gila NF, becoming more NE/ENE
further north over the Sangre de Cristo Mountains. The eastern plains
will remain dry as a result, outside of storms moving east off the
Sangre de Cristo's over far northeastern NM.

LONG TERM...(SUNDAY THROUGH THURSDAY)...
High pressure aloft is expected to be centered over the Gulf Coast on
Sunday with the upper low just offshore of WA/OR. This will keep a
light SSW to NNE flow over NM with above average PWATs (generally 0.8
to 1.1 inch) forecast to linger over much of the forecast area. The
mid level flow will not be all that strong and some erratic
deviations could occasionally drift up into the southern to central
parts of the state while northern zones would be more prone to
observe faster paced cells. Storms would follow a fairly
climatological spatial distribution, being most concentrated from the
southwestern to the northern mountains Sunday afternoon with locally
heavy rainfall being at the forefront of concerns, and of course
subsequent burn scar flash flooding.

Little movement or alteration with the upper level features in the
Pacific Northwest states and the Gulf Coast will result in only small
modifications to the thunderstorm coverage on Monday. The Sacramentos
could observe higher chances, but remaining zones would fare
similarly to Sunday per a blend of POP guidance. A possible weak
shortwave arriving from the south could bring PWATs up more, but
confidence is not all that high on the specifics with this potential
perturbation.

The upper high will begin to sprawl over more of the southeastern
states into Tuesday and Wednesday. Some drier air may eventually work
into northwestern zones by Wednesday, but overall the coverage and
distribution of storms is not expected to alter too much. However,
into Thursday and more-so into Friday, the upper high is projected to
re-establish itself over the Four Corners. This would imply
potentially more drying in northwestern NM zones, and with the
strength of the high expected to exceed 600 decameters by Friday,
subsidence would pose much more difficulty for storms to form.

24/52

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.FIRE WEATHER...
Daily rounds of afternoon convection increase in coverage and
intensity today and through the Fourth of July holiday. The monsoon
plume is situated more directly over New Mexico, allowing for the
greater coverage in storms along with higher atmospheric moisture
producing good to excellent recoveries. Afternoon storms will
initiate over the high terrain first, before drifting over
surrounding lower elevations. Steering flow will be weakest over
western NM, becoming NE/ENE 5-15 mph over the northern mountains.
With all factors considered, the threat of burn scar flash flooding
increases today through the first half of next week. Thereafter, the
upper high slowly loses shape and begins redeveloping over the Four
Corners and UT late next week. A steady downtrend in storm coverage
is expected, with backdoor frontal intrusions into eastern NM
favored.

24

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.ABQ WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 9 PM MDT this evening for the following zones...
NMZ208-211-214-215-229-241.

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