Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/31/21
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
819 PM MDT Sun May 30 2021
Severe thunderstorm watch 225 has expired. Updated Wx grids to
reflect current trends. Still looks like scattered showers and
thunderstorms may linger through the overnight hours. ZFP already
.PREV DISCUSSION...515 PM MDT Sun May 30 2021...
00Z TAF CYCLE
Low level moisture will continue to make a run west and northwestward
through the RGV and to the Continental Divide and into northwest NM.
A few drier showers and storms with wind gusts to around 45kt will
prevail over portions of nw and west central NM as well as the RGV.
From the central mt chain ewd, convection was becoming less
widespread at 23Z but a few storms will continue to be severe with
large hail and wind gusts to 50kt through 02Z. Higher terrain will
become obscured in widespread MVFR to IFR cigs/vbys in br and
precipitation developing by 06Z from the central mt chain to the TX
border. Improvement is expected to be slow between 31/13-17Z.
.PREV DISCUSSION...304 PM MDT Sun May 30 2021...
Strong to severe thunderstorms are possible across portions of
eastern New Mexico today. Locally heavy rainfall, damaging wind, and
large hail are the primary threats. Another round of afternoon
showers and thunderstorms will be possible over Memorial Day for much
of northern and central New Mexico. Temperatures will be cooler than
normal for most of the forecast area with isolated showers and
thunderstorms possible each afternoon this week. Temperatures will
trend warmer towards the weekend, bringing most locales near to
slightly below normal.
SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)...
Low level moisture made a run farther west as well as up the Rio
Grande Valley last night and this morning. While some of this has
finally started to mix out this afternoon, enough has survived to
pop a few cells over and near the Valley as well as over Rio Arriba
County. Some of this activity should be dry with gusty erratic
winds. Elsewhere, the threat for strong to severe storms east of the
central mountain chain continues for the rest of the afternoon.
Locally heavy rain remains a threat, although cells have not been as
prolonged in one place has the one this morning north of Tucumcari
to Logan. Considered whether or not the current Flash Flood Watch
needed to be expanded but models indicating mixed messages. The
NAM12 is indicating a west to east oriented swath of precipitation
over portions of east central NM late this evening but the HRRR is
shunting the majority of the heavy precipitation into TX around 00Z.
Therefore will let the current Watch ride. On Memorial Day,
northwest flow is forecast over north central and northeast NM as
low level moisture continues to leak westward, therefore the focus
for heavy rain may be more over the northern mountains and northeast
Memorial Day, where locally heavy rainfall has been inserted in the
weather grids. The severe threat is forecast to be more limited
Memorial Day to southeast NM, at least at this time per the SPC Day
2 Outlook. Otherwise, low clouds and fog will return to the east
tonight and where high temperatures Memorial Day will be much cooler
LONG TERM...(TUESDAY THROUGH SUNDAY)...
Upper level low pressure in the Baja will continue to spin in place
on Tuesday as a disturbance digs into northern NM. Shower and
thunderstorm chances will be favored across the eastern slopes of the
central mts before pushing off into the eastern plains in the
afternoon. With steep 700-500 mb lapse rates of around 8 deg/km and
CAPE values between 800 to 1200 J/kg, a few storms may become strong
with isolated hail and damaging wind. Wednesday offers a similar
setup as the upper low maintains its anchor in the Baja while the
trough in the Midwest continues to swing its axis to the east.
Another round of afternoon showers and thunderstorms will be on tap
for the central mts and eastward as the west remains mostly dry. The
exception might be across portions of southwest NM, where some
residual moisture may help to support some limited convection, though
accumulations of more than a few hundredths of an inch look
unlikely. By Wednesday night, an area of high pressure forms near the
Great Basin, forcing the western portion of the CONUS into a Rex
block. This will allow for moisture to continue to be pulled in from
the Gulf and for the daily rounds of showers and thunderstorms to
persist through the end of the week. While coverage across areas west
of the central mt chain looks more favorable, it is not very well
resolved by models at this stage in the game. The Rex block degrades
on Saturday, shifting the pattern into a less favorable moisture
regime for the Land of Enchantment. Models diverge at this point,
with the GFS displaying the cutoff low wandering through the Baja
while the ECMWF develops a ridge across the Desert Southwest and the
CMC brings an amplified low in off the coast of CA. Evolution of
these upper level features will dictate the possibility of continued
precipitation coverage towards the end of the long term. Otherwise,
temperatures will trend below average through next week for most
locales, the exception being the west which will be near to above
Low level moisture has leaked into the Rio Grande Valley and
Northwest Mountains last night and this morning, allowing for some
mostly dry showers and storms with erratic winds between the Rio
Grande Valley and Continental Divide through this evening. Moisture
will continue to seep westward tonight and Memorial Day where
chances will increase for wetting rain with any convection.
From the central mountain chain eastward, wetting showers and storms
will continue though Memorial Day. Some of the storms will be strong
to severe during the afternoons and evenings and some may contain
locally heavy rain, which could lead to flooding. Flooding is a
concern for any burn scars along the east slopes of the Sangre de
Cristo mountains for the rest of this afternoon and evening.
Overall, humidities will trend up and temperatures down on Memorial
Day. Areas of poor ventilation are forecast from the central
mountain chain eastward Memorial Day and Tuesday while rates over
the west will be mostly good to excellent.
An upper ridge may begin to dominate the state by the middle of the
week, but enough moisture will linger for daily rounds of showers
and storms, focused over the mountains and east. However, chances
for wetting rain gradually diminish from day to day. High
temperatures will trend warmer again and humidities lower.
Flash Flood Watch until 10 PM MDT this evening for the following
Area Forecast Discussion
National Weather Service Amarillo TX
625 PM CDT Sun May 30 2021
00Z TAF Cycle
VFR conditions will quickly become MVFR to IFR between 00Z and 04Z
Monday. Showers and thunderstorms will be on the increase at all
three TAF sites between 00Z and 06Z Monday which will continue
through 00Z Tuesday. Thunderstorm wind gusts of 40 to 50 knots or
higher will be possible with the strongest thunderstorms between
00Z Monday and 06Z Monday. IFR to MVFR conditions will prevail
with some LIFR and VLIFR conditions in the heavy rainfall.
Southeast winds 15 to 25 knots with gusts near 30 knots will
become north to northeast 5 to 15 knots after 04Z to 06Z Monday.
.PREV DISCUSSION... /Issued 356 PM CDT Sun May 30 2021/
SHORT TERM...Tonight through Monday...
The two big questions of the day (1 will the clouds break and 2
will the boundary across the north hold there and not push through
the CWA) have now been answered - yes and yes. This appears to be
setting the stage for a widespread thunderstorm event with
potential for severe storms and very heavy rainfall tonight which
that the CAMS are finally seeming to agree on at least a little
The jet exit region will move across the area overnight with good
upper diffluence spreading across the area. Multiple S/WVs moving
around the base of a deep trough in AZ S/WVs will continue to
move across the area through Monday. With low clouds scattering
out, temperatures have increased into the 70s most areas and ML
CAPE is around 1000-1500 J/KG and is forecast to reach 1500-2000
J/KG for most of the area by 00Z. There is good low level turning
in the wind fields and around a 90 kt upper level jet that will
move into the area, but the RAP progs of just 25-30 kt effective
bulk shear seems a tad low this evening especially given NAM pros
of 30-60 kt 0-6 km shear ahead of the storms. Convective
initiation is already occurring along the higher terrain of NM and
the outflow boundary across the north will be another potential
focus area. Discrete supercells are possible mainly in the west,
but appears these will be pretty quick to congeal into an MCS that
will have very good h85-h7 theta-e advection to feed this complex.
Given all this, all hazards are possible but the greatest hail
and tornado threat (5% per SPC) will be in the west before MCS
development. Very heavy rainfall is expected and much of the area
may see 1 to 3 inches (W/ locally higher amounts possible) in a
short period of time. The intersection of the outflow boundary and
the MCS could be an area to watch for highest rainfall totals as
well as greater tornado threat as well as the SE where many HREF
is pinging on higher potential for 2+ inch rainfall. A flood watch
has been issued for the entire region given the high rates
Best upper dynamics and strongest S/WV assoc w/ the upper system
might actually occur early Monday and therefore POPs remain
relatively high despite being on the backside the overnight MCS.
That said, storm intensity and rainfall rates should be much less
Monday and therefore the Flood Watch is set to expire at 12Z for
now. Cool outflow will fill in behind the storm complex w/ NRLY
winds developing and this will keep the area cool, cloudy and damp
on Monday with low clouds and SCT shra/tstms persisting.
LONG TERM...Monday night through Saturday
Open wave to move across the Panhandles Monday night keeping chances
for convection Monday night across most of the forecast area.
Upper trough will begin to shift east away from the Panhandles
Tuesday with the upper flow transitioning to northwesterly behind
the departing upper trough. Lingering convection possible Tuesday.
Perturbations within the northwesterly or north northwesterly
upper flow aloft Wednesday through Friday will bring chances for
convection again during the afternoon into the nighttime hours
during the latter half of the week. Upper high builds in over the
Great Basin region late in the week with a more northerly and even
a northeasterly upper flow expected across the Panhandles by
Friday and Saturday.
Surface ridge builds down from the north into the forecast area
early this week. Surfaced ridge to kick out to the south and east
by the middle of the week as surface low pressure develops to the
lee of the Rockies in eastern Colorado and eastern New Mexico.
Surface flow to transition from upslope southeasterly to more
southerly and southwesterly by the middle and end of the week.
Frontal boundary to the south of the Panhandles by the middle of
the week forecast to lift north and east near or into the
Panhandles before frontolysis occurs by Thursday or Friday. Any
residual surface boundaries across the Panhandles late this week
will be a focus for lift for diurnally- driven convection.
Weakness in the upper flow along with diurnal heating and ample
residual low level moisture, with dew points in the 50s and 60s,
will result in convection still not out of the equation Friday
afternoon and evening as well as Saturday afternoon and evening.
Early in the week, some of the stronger convection could still be
efficient rainfall producers.
TX...Flood Watch through Monday morning for the following zones:
OK...Flood Watch through Monday morning for the following zones:
Area Forecast Discussion
National Weather Service Duluth MN
728 PM CDT Sun May 30 2021
.DISCUSSION...(This evening through Saturday)
Issued at 447 PM CDT Sun May 30 2021
Summary: ongoing showers and thunderstorms will continue through
the afternoon and evening hours today, with more chances of storms
over northwest Wisconsin Monday. Temperatures will continue to
warm up through the week, with highs in the 80s to near 90 by next
The main focus in the short-term will be on chances of showers and
thunderstorms this afternoon, continuing through the evening
hours, as we remain under a mid-level trough, with embedded
shortwaves. The first round of storms is moving through from just
south of Grand Rapids extending northeast towards Ely. This
activity formed in the destabilized area of north-central
Minnesota where more insolation was observed. The better
environment for strong to severe storms remains to the west of the
forecast area, where mid-level lapse rates of 7 to 8 degrees C/km
exist. Surface-based CAPE values of 500 to 1000 J/kg based on the
RAP analysis are present, but deep-layer shear between 20 to 30
knots isn`t the most supportive of convective updrafts. So far, we
have received reports of small hail and perhaps some gusty winds
to around 40 mph. As we go into the evening hours, the main cold
front boundary will slide eastward, which will support another
round of showers and storms. If we receive severe storms, this
will be the most likely area for it. Damaging winds and large hail
up to 1" in diameter will be the most likely threats. The front
will continue to track southeast tonight into Monday, along with
the mid-level shortwave trough lingering over the Northland.
Models are indicating another round of showers and thunderstorms
over northwest Wisconsin along the boundary. Mixed-layer CAPE of
500-1000 J/kg will once again be present, but deep-layer shear
will range between 20 to 30 knots. The latest run of the CAMs
appear to indicate the thunderstorm activity will be largely out
of our forecast area, although we can`t entirely rule out a
westward shift in the activity. For now, the signal is strong
enough for the Storm Prediction Center to pull out the Marginal
(low-end) Risk of severe weather from northwest Wisconsin.
Elsewhere, dry conditions are expected, under partly to mostly
Dry conditions are expected across the region for Tuesday, thanks
to high pressure and upper-level ridging over the region. Although
we have dry relative humidity values between 20 to 30 percent,
winds will remain on the light side, so not anticipating elevated
fire weather concerns. We will have another chance for Tuesday
night through Wednesday as a mid-level trough returns to the
Northland. Some thunderstorms may develop, particularly Wednesday
afternoon, but instability appears to be very modest, along with
little, if any, deep-layer shear.
Conditions will be mostly dry for Thursday through next weekend,
thanks to large-scale ridging over the upper Midwest. The main
story for next weekend will be on increasing temperatures - likely
the warmest temperatures we have seen thus far this year. High
temperatures will warm into the 80s on Friday, with some upper 80s
and lower 90s possible Saturday and Sunday.
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 728 PM CDT Sun May 30 2021
There will be a chance for strong storms this evening then some
fog and low MVFR and IFR ceilings in spots overnight. Area radars
showed showers and thunderstorms across northern Minnesota this
evening and this will continue through at least the late evening
hours as an upper trough, surface trough, and cold front all move
through the region tonight. Instability and deep layer shear have
been limiting factors so far in producing severe thunderstorms but
a few of the stronger storms have been capable of producing hail
form pea to penny size and gusty winds to 40 mph. We expect this
to continue for a few more hours before they weaken. It`s possible
a storm could still go severe with large hail and damaging wind
the main threats. Later tonight, an area of fog and low MVFR or
IFR ceilings will develop, most likely to affect the
KHIB/KDLH/KHYR TAFs. The fog and IFR ceilings will lift Monday
morning leading to VFR conditions.
Issued at 330 PM CDT Sun May 30 2021
The main focus across western Lake Superior for this afternoon
into tomorrow will be on increasing chances of thunderstorms,
especially for early this evening and overnight. A trough of low
pressure will gradually make its way eastward tonight, resulting
in this activity. The threat for severe weather remains low over
the nearshore waters, but a strong storm capable of stronger winds
and hail can`t be ruled out, along with cloud-to-water lightning
with any thunderstorm. The thunderstorm activity is expected to
begin around 6 to 7 PM CDT tonight lasting through just after
midnight. There is another chance of thunderstorms Monday
afternoon, mainly over the South Shore. Severe weather is not
anticipated, but some stronger wind gusts and small hail can`t be
.PRELIMINARY POINT TEMPS/POPS...
DLH 46 69 47 74 / 60 20 0 0
INL 43 71 45 79 / 60 0 0 10
BRD 46 72 47 77 / 30 10 0 0
HYR 47 71 43 76 / 20 30 0 0
ASX 48 70 45 75 / 30 20 0 0
Area Forecast Discussion
National Weather Service Memphis TN
1102 PM CDT Sun May 30 2021
See the 06z aviation discussion.
.PREV DISCUSSION... /issued 841 PM CDT Sun May 30 2021/
No major updates to the forecast. High thin cirrus continue to
spill into the region from the northwest. Unless these clouds
thicken, they should have little effect on radiational cooling
overnight. Weak surface high pressure remains in place and winds
have gone calm across much of the forecast area in the past hour.
Temperatures are progged to fall into the upper 40s near the
Tennessee River, with low to mid 50s across the rest of the area.
Forecast is on track with very minor adjustments to temperatures
and cloud cover.
PREV DISCUSSION... /issued 318 PM CDT Sun May 30 2021/
Beautiful weather will continue for the holiday weekend. SFC high
pressure currently located over the Ohio Valley will begin to
shift east. Winds will begin to turn around to the southeast by
tomorrow, but first expect another cool night with lows in the
upper 40s to mid 50s. Temperatures will quickly begin to climb in
the morning thanks to the southeasterly winds. Highs will range
from the upper 70s to lower 80s.
Upper flow aloft will become more southwesterly by Monday Night as
an upper trough begins to dig in the Central and Southern Plains.
A shortwave will rotate through the flow and could set off some
showers across Eastern Arkansas and the Missouri Bootheel as early
as the overnight hours Monday Night. The HRRR seems the most
progressive of the CAM models in regards to timing of the
shortwave. Have added 20 POPS for after midnight Monday Night for
The shortwave will move across Northeast Arkansas, the Missouri
Bootheel and Northwest Tennessee on Tuesday into Tuesday Night.
Showers and thunderstorms will develop in association with the
shortwave, but will mainly affect areas along and northwest of a
Clarksdale, Mississippi to Paris, Tennessee line.
The cold front will move into the area by Wednesday and Wednesday
Night and stall over the area until the upper trough moves into
the region to push the front east on Thursday. The front will be
the main focus of shower and thunderstorm development during this
Models diverge by Thursday. The GFS and Canadian models develop
an upper low within in the upper trough that could meander around
the Mid-South through next weekend. Meanwhile, the ECMWF builds
an upper ridge over the Central and Southern Plains by the end of
the week. Left chance POPS in the forecast from Thursday Night
through next weekend. Even if the ECMWF solution ends up being
correct, there will be chances for diurnal convection during that
time frame. Overall, temperatures will range from the upper 70s to
the upper 80s over the course of the next 7 days.
Light northeast winds will veer from the southeast by mid-morning
Monday but will generally remain 7 kts or less. A few Cu are
expected tomorrow with prevailing VFR conditions. High clouds will
increase late tomorrow with mid-level ceilings developing toward
Tuesday morning as the next system approaches the Mid-South.
Area Forecast Discussion
National Weather Service Marquette MI
625 PM EDT Sun May 30 2021
.SHORT TERM...(This evening through Monday)
Issued at 409 PM EDT SUN MAY 30 2021
WV imagery and RAP analysis indicated a mid/upper level trough from
Hudson Bay into the eastern Dakotas. A lead shortwave into western
Upper Michigan and northwest WI has brought some light showers with
rainfall amounts of a trace to a few hundredths of an inch. Even
though the the precipitation was diminishing as it moves eastward
into the drier airmass, a few sprinkles of light showers may still
move through central Upper Michigan late this afternoon. A stronger
compact well-defined shortwave over southern Manitoba supported
sct/nmrs showers and thunderstorms into northern Minnesota with some
wind gusts of 40-50 mph in far nw MN.
Tonight, although the shra/tsra over northern MN are likely to
weaken this evening with the loss of daytime heating some may
survive into western Upper Michigan overnight as the Manitoba shrtwv
approaches. Min temps will only fall into the mid and upper 40s with
more clouds and low level WAA.
Monday, similar to what was observed upstream, expect shra/tsra to
develop and expand in coverage by midday into the afternoon over
central Upper Michigan as daytime increases. Even with mostly
cloudy skies and temps to near 70, cold mid levels (500 mb temps
to -23C) may result in MUCAPE values of 500-1000 J/Kg. Despite the
relatively weak 0-6km shear in the 25-30 knot range, some strong
storms could develop given the steep mid level lapse rates of
7.5-8.0 C/Km. Marginally severe hail, generally at or less than an
inch, will be possible with freezing levels only around 8k ft.
Wind gusts at or above 40 mph may also be possible given upstream
.LONG TERM...(Monday night through Sunday)
Issued at 416 PM EDT SUN MAY 30 2021
Monday evening will bring the upper level shortwave trough axis
swinging through the northern Great Lakes region. This will result
in lingering showers and convection across the southern half of
Upper Michigan, with an area of focus primarily near the WI/MI
border. Upper level steering flow will be primarily from the nw to
the se, and movement of the lingering showers and thundershowers
will quickly propagate toward Lake Michigan by 3Z Tuesday. PW values
are not impressive, with values ranging between 0.5 to 0.75 inches.
Thus, a heavy rain shower isn`t likely to amount to appreciable
levels over the observation sites. With the SPC having a portion of
Upper Michigan in the Day 2 Marginal Risk, the threat for widespread
severe criteria convection looks minimal especially toward evening
as the instability will begin to waver near sunset on Monday evening.
For Tuesday, weak upper level ridging will occur. Temperatures will
rebound nicely, compared to Monday after the cold front moved
through Upper Michigan, for afternoon highs where low to mid 70s are
likely. Guidance is signaling the diurnal lake breeze causing
surface convergence in the east half of Upper Michigan Tuesday
afternoon. A few diurnal cu are possible to create some possible
light rain sprinkles or a brief rain shower in this area. MUCAPE
values are below 500 J/kg, so instability is unlikely to assist with
persistent rain shower activity.
Another shortwave disturbance will approach the Great Lakes
on Wednesday, bringing another opportunity for rain showers over the
area. Medium range guidance continues to show split flow regimes
where the jet stream energy will remain both north and south of the
Great Lakes area concerning our cwa at this time of inspection. With
a surface low expected to be north of Upper Michigan, this will keep
the area in the warm sector. Southerly flow will assist with
afternoon highs being slightly warmer on Wednesday, where
temperatures up to the Lake Superior shoreline are likely to
approach the lower to mid 70s, with slightly warmer temperatures
further inland. Thursday looks mostly dry, despite a weak shortwave
embedded in the flow aloft. Afternoon diurnal showers/from the lake
breeze may occur over the east half of the area, but the potential
remains low for total rainfall at this time.
Friday through the weekend will bring much warmer temperatures to
the area as model consensus is trending toward a building upper
level ridge over the Upper Midwest. Very warm temperatures will be
possible over Upper Michigan, possibly the warmest temperatures of
the season thus far. The southerly flow will cause the areas prone
to downsloping in Marquette/Alger County to experience slightly
higher temperatures compared to the shoreline along Lake Michigan.
Several areas may eclipse the 90 degree mark if ensembles members
come to fruition in the coming 5 to 7 days.
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 624 PM EDT SUN MAY 30 2021
VFR conditions are expected to continue through the period at SAW
and CMX. As showers move in late tonight into Mon morning over
western Upper MI ahead of an approaching trough, cigs will lower to
MVFR at KIWD briefly, otherwise will be VFR through most of the
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 409 PM EDT SUN MAY 30 2021
No real marine concerns as winds of 20 knots or less are expected
into next week. High pressure to the northeast will be the dominant
force over the region through the rest of the weekend. Late Monday,
a weak cold front will swing through the region and could produce
showers and maybe a few thunderstorms, but will then be replaced by
more ridging and dry weather by midweek.
Area Forecast Discussion
National Weather Service Pocatello ID
202 PM MDT Sun May 30 2021
.SHORT TERM...Tonight through Tuesday night. Upper ridge continues
to build across the region through the short term. For the
remainder of this afternoon into the evening, there are some
afternoon build-ups over the central mountains and the highlands
near the Bear Lake area. High-res models are in some disagreement
as to which of these area, if any, will produce any development of
significance. Latest HRRR favors a cell or two shifting out of the
central mountain area into the INL portion of the Snake Plain.
Nested NAM appears to favor the southeast corner. Neither are
inspiring much confidence, especially considering the dry
forecast from other high-res solutions. This should be the last
chance to see any concern for precip through the short term as the
upper ridge continues to strengthen. Temperatures will continue
to trend upwards through the short term. DMH
.LONG TERM...Wednesday through Sunday.
Upper level ridge overhead Wednesday with very warm temperatures
expected and highs in low elevations near 90. Ridge axis slides
slightly east Thursday and expect even warmer temperatures with many
areas well into the 90s and at or near record high temperatures.
May see a slight chance of showers and thunderstorms thursday and
Friday mainly in high elevations. Expect slightly cooler conditions
Saturday and Sunday but highs in the 80s still Friday and Saturday.
Could be near seasonal normals by Sunday. May see again a slight
chance of showers and thunderstorms on Sunday. Confidence low in
precipitation chances next weekend.
Will have widespread VFR conditions continuing through Monday with
mainly clear skies. Winds at sites will generally be in the 5 to 10
knot range in the afternoons.