June 2023

[DoctorMu]

I lived in Baton Rouge for a few years. Sometimes the Texas Death Ridge affected their summer weather. Some years not so much.

[DoctorMu]

We'll see if the anomaly continues, but this is a top 5% June in temperature over the past 30-40 years, especially when combined with a very high DP. It looks there there will be some normalizing within the next week, returning to near seasonable values which are still very hot. I hope the DPs drop some to make outdoor activity more tolerable and less dangerous.

[user:null]

Mexico is an area where deserts occur. Deserts are usually in mid latitude areas between 30 to 50 degrees latitude. There is also the Hadley Cell, which causes air to sink at around 30 degrees. Mexico is also mountainous, in which moisture is blocked from the Pacific. The windward side is wetter, while leeward side is drier. Ocean water plays a role in desert, which is not the case with Mexico.

Heat ridges do occur around the world. There is the Saharan Heat Ridge, Azores High, Bermuda High, and Sonoran Heat Ridge. Oceans do play a role in heat ridges. They occur in the subtropical areas north or south of the equator.

Desert Biome
https://askabiologist.asu.edu/explore/d ... th%20poles.

Climatology Of Heat Ridges Affecting Europe And North America
https://groups.google.com/g/weatheramer ... SwUPE7mkM0

What is a heat dome?
https://oceanservice.noaa.gov/facts/heat-dome.html

Hadley Cells
https://groups.seas.harvard.edu/climate ... adley.html

Thank you.

I enjoyed this detailed writeup, and especially liked the articles (particularly the descriptive one from Larry Cosgrove). What I was also trying to get at, though, is the understanding regarding factors that influence precisely where the ridges set up. Basically, predicting heat ridge locations the same way that we have indexes like ENSO, PNA, EPO, NAO, etc regarding the influences regarding mid-latitude storm tracks during winter-spring: there's the MJO for the tropics, but I'm wondering the effects on heat ridge formation from that.

That said, there may be combinations of features abound. It is said that hot land causes the rising warm air that raises pressure surface heights ... but as you mentioned, there are also heat ridges right over ocean, despite how much more moderated the water is compared to the land.

Not to mention seasonal variations. For instance, the common description you give regarding the Hadley Cell and sinking ~30°N and S from the equator. But it should be specified whether that is a permanent state of affairs, or whether that is merely just an average on account of seasonal weather pattern shifts throughout the year (i.e. jet stream moving equatorward/poleward with the seasons). If indeed the latter, then there will certainly be a factor that limits the poleward extent of Hadley cells, jetstreams, etc during the hot season.

Overall 30-50° is quite a range in latitude: these types of ridges in Texas summers, and the heatwaves that follow, seem to occur too frequently in/near the state to be a purely randomized factors across the latitudinal range. For what it's worth, there's an alternative hypothesis for desert formation known as the RH Mechanism designed to account for deficiencies regarding the Hadley Cell explanation: while the RH was proposed with the Asian continent in mind, it's possible that the processes described could occur worldwide during summer (including for the heat ridges in Texas).

[Ptarmigan]

Mexico is an area where deserts occur. Deserts are usually in mid latitude areas between 30 to 50 degrees latitude. There is also the Hadley Cell, which causes air to sink at around 30 degrees. Mexico is also mountainous, in which moisture is blocked from the Pacific. The windward side is wetter, while leeward side is drier. Ocean water plays a role in desert, which is not the case with Mexico.

Heat ridges do occur around the world. There is the Saharan Heat Ridge, Azores High, Bermuda High, and Sonoran Heat Ridge. Oceans do play a role in heat ridges. They occur in the subtropical areas north or south of the equator.

Desert Biome
https://askabiologist.asu.edu/explore/d ... th%20poles.

Climatology Of Heat Ridges Affecting Europe And North America
https://groups.google.com/g/weatheramer ... SwUPE7mkM0

What is a heat dome?
https://oceanservice.noaa.gov/facts/heat-dome.html

Hadley Cells
https://groups.seas.harvard.edu/climate ... adley.html

Thank you.

I enjoyed this detailed writeup, and especially liked the articles (particularly the descriptive one from Larry Cosgrove). What I was also trying to get at, though, is the understanding regarding factors that influence precisely where the ridges set up. Basically, predicting heat ridge locations the same way that we have indexes like ENSO, PNA, EPO, NAO, etc regarding the influences regarding mid-latitude storm tracks during winter-spring: there's the MJO for the tropics, but I'm wondering the effects on heat ridge formation from that.

That said, there may be combinations of features abound. It is said that hot land causes the rising warm air that raises pressure surface heights ... but as you mentioned, there are also heat ridges right over ocean, despite how much more moderated the water is compared to the land.

Not to mention seasonal variations. For instance, the common description you give regarding the Hadley Cell and sinking ~30°N and S from the equator. But it should be specified whether that is a permanent state of affairs, or whether that is merely just an average on account of seasonal weather pattern shifts throughout the year (i.e. jet stream moving equatorward/poleward with the seasons). If indeed the latter, then there will certainly be a factor that limits the poleward extent of Hadley cells, jetstreams, etc during the hot season.

Overall 30-50° is quite a range in latitude: these types of ridges in Texas summers, and the heatwaves that follow, seem to occur too frequently in/near the state to be a purely randomized factors across the latitudinal range. For what it's worth, there's an alternative hypothesis for desert formation known as the RH Mechanism designed to account for deficiencies regarding the Hadley Cell explanation: while the RH was proposed with the Asian continent in mind, it's possible that the processes described could occur worldwide during summer (including for the heat ridges in Texas).

Your welcome. I am sure that MJO has some factor on heat ridge. Ocean water temperature gradient do play a role in heat ridge.

What is a heat dome?
https://oceanservice.noaa.gov/facts/heat-dome.html

On the topic of deserts, some of the driest deserts are on the coast. Atacama and Namib Desert come to mind. They are dry because the water is cooler. Atacama Desert has the Humboldt Current, while Namib Desert has Benguela Current. They are cold water currents.

Ocean Circulation and Atmospheric Circulation
https://www.thephysicalenvironment.com/ ... 0be%20made.

Tibet is dry because moisture from the Indian Ocean is blocked by the Himalayas. On the windward side, it is very wet. Some of the wettest areas in the world are in India, due to monsoon. Seattle and Anchorage are drier due to mountains areas. Mount Olympus, which is west of Seattle is the wettest area in the Lower 48. Anchorage has rain shadows due to the mountains west and south of the city. If there were no mountains in western Mexico, I suspect, there would be less desert in Mexico.

The 5 Wettest Places On Earth
https://www.worldatlas.com/climate/here ... earth.html

[user:null]

We'll see if the anomaly continues, but this is a top 5% June in temperature over the past 30-40 years, especially when combined with a very high DP. It looks there there will be some normalizing within the next week, returning to near seasonable values which are still very hot. I hope the DPs drop some to make outdoor activity more tolerable and less dangerous.

Yeah. Need more relief, so we don't get 130°F heat indices like Kingsville Naval Air Station (near Corpus) saw yesterday.

[Stratton20]

The 12z EPS keep a strong death ridge over the state through the next 2 weeks but the 12z GEFS weakens it significantly and shifts the ridge westward

[DoctorMu]

We'll see if the anomaly continues, but this is a top 5% June in temperature over the past 30-40 years, especially when combined with a very high DP. It looks there there will be some normalizing within the next week, returning to near seasonable values which are still very hot. I hope the DPs drop some to make outdoor activity more tolerable and less dangerous.

Yeah. Need more relief, so we don't get 130°F heat indices like Kingsville Naval Air Station (near Corpus) saw yesterday.

Kingsville - A&M has a branch there. 106°F with 80°F DP yesterday. Ridiculous. Currently, there is a mere 123°F heat index in Kingsville.

[DoctorMu]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
301 PM CDT Sun Jun 18 2023

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(This evening through Monday Night)
Issued at 236 PM CDT Sun Jun 18 2023

Key Messages:
- Excessive Heat Warning (majority of Southeast TX)/Heat Advisory
(coastal Jackson/Matagorda Counties) remains in effect thru 8pm CDT
Monday evening.
- Dangerous heat will continue through at least midweek.
- Marginal to slight risk of severe weather in the late
afternoon/early evening for portions of the Brazos Valley/Piney
Woods area today.
- Hazardous beach conditions continue with a high risk of rip
currents along Gulf-facing beaches through at least this evening.

If you read my AFD update this morning and checked out the latest
obs (at least the dew points), you`ll see that I kinda jinxed
something. I mentioned that dew points were having trouble mixing
out even with a 30-35 kt southwesterly LLJ overhead...I should`ve
waited a couple of hours because now we have the "best" mixing we`ve
seen over this period of excessive heat. Dew points as of 2pm CDT
have dropped to as low as the low 70s, [I'd not seeing this - mid 70s in CLL] which doesn`t sound like much
but it makes quite the difference in the heat index values.
Additionally, we have widespread relative humidity values near or
below 50%. We`re still comfortably into the 100s heat index wise
though, but not seeing a large amount of heat index values well into
the 110s [113°F HI here] as we`ve recently seen over this period.

Regardless of all of that, it is still dangerously hot and will
continue to be so into the new week. Please be sure to take the
necessary precautions to stay safe from the heat: drink plenty of
water, take frequent breaks, avoid strenuous outdoor activities
during the hottest part of the day, and ALWAYS ALWAYS ALWAYS look
before you lock your vehicle. Don`t forget about your pets as well!
If the ground is too hot for the palm of your hand, then it is too
hot for their paws.

The upper level high providing the strong ridging aloft (will be
referred to as heat dome from here on out) will gradually nudge
northward into Monday. So...even hotter temperatures are in the
forecast. Before that though, let`s talk about a front and some
storm potential. If you live south of the Brazos Valley/Piney
Woods... [aka Hwy 1*5] you can go ahead and skip to the next paragraph. A weak
quasi-stationary frontal boundary will nudge ever so slightly
southward late this afternoon/evening. This will serve as an
initiation point for storms to develop off of and push southward
into our far northern locations. There is a subsidence inversion
layer aloft that will gradually dissipate these storms, but there is
fairly good consensus in the 12Z CAMs of at least some convection
surviving into the Brazos Valley/Piney Woods.[Don't Lucy me again!!] Some of these storms
could be strong to severe with hail and strong winds as the primary
hazards. As a result, SPC has this region in a slight (level 2 out
of 5) to marginal (level 1 out of 5) risk of severe weather.

Back to the heat! We`ll trade up today`s 588-590 dam 500mb heights
to 590-593 dam by Monday as the heat dome continues to nudge
northward. NAEFS/GEFS indicate 700mb/850mb temperatures will be at
their MAX percentiles. Suffice to say...Monday looks to be our first
day in the triple digits of the year (for the city of Houston). The
average first day for reaching the 100°F mark for Space City is July
19th...so if the forecast verifies we`d beat that by a month.
Expecting temperatures across Southeast TX to top out in the upper
90s to low 100s for Juneteenth. Heat index values will max out in
the 110-115°F range, so the Excessive Heat Warning remains in effect
for most of Southeast TX through Monday evening. Temperatures during
the overnight hours will still be rather warm with lows in the upper
70s to low 80s...yuck. Astronomical Summer begins this Wednesday
(June 21st), but that feels like just a formality at this point...

Lastly, I`d like to say Happy Father`s Day to all of the dads out
there! Thanks for all that you do. Please continue to practice heat
safety as this period of excessive heat continues. Stay safe, stay
cool, stay hydrated.

Batiste

&&

.LONG TERM...
(Tuesday through next Saturday)
Issued at 236 PM CDT Sun Jun 18 2023

No significant changes made to the ongoing fcst. Will probably
have Excessive Heat Warnings/Advisories ongoing into midweek.
Strong ridge over northern Mexico and sw Tx slowly migrates
westward Wed-Fri. As it does so, heights will ever so slightly
fall and should see a corresponding temp reduction...but it`ll still
remain unseasonably hot. May see some slightly drier air try to
backdoor into some inland parts of the area late Wed & Thurs. This
boundary may serve as a focus for some iso/sct convection toward
peak heating during the second part of the work week if we are
able to get those H85 & H7 temps down far enough. Unfortunately,
it appears the ridge could expand back east over the weekend
bringing readings right back up & rain chances back down to
minimal/nil. Once these summer ridges get set up, they`re tough to
break down & some of the extended ensembles show above normal
heights for the next couple weeks. 47

&&

.MARINE...
Issued at 236 PM CDT Sun Jun 18 2023

Moderate southerly winds and 3 to 5 foot seas are expected
through the early parts of the week then slightly diminish. Rain
and storm chances will remain close to zero into midweek, then
only modest chances toward the later part of the work week.

Will maintain the caution flags for the bays into mid evening and
offshore overnight to capture the diurnal wind maximums. Galveston
Beach Patrol is flying the red flags so will maintain the high rip
current risk this evening then re-evaluate things for maybe
another one tomorrow. 47

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1134 AM CDT Sun Jun 18 2023

Breezy southerly to southwesterly winds with occasional gusts
around 20-25 knots will continue through sunset then gradually
lighten as they trend towards becoming light and variable at most
sites. High-resolution model guidance points towards scattered
storms moving in from the north going into the early evening hours
and rapidly losing steam as it does so. UTS has highest
probability of seeing any remnants from this, so VCTS has been
added to their TAF. The light and variable winds should help lead
to another night with patchy fog...so far only CXO and LBX have
6SM BR to hint at this scenario. Most sites will see MVFR ceilings
develop overnight between 08Z-14Z before clouds begin to clear
out as southerly/southwesterly winds begin to pick up again on
Monday morning.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 78 100 78 101 / 20 0 10 0
Houston (IAH) 79 100 80 101 / 10 10 0 0
Galveston (GLS) 83 90 82 91 / 10 0 0 0

[MontgomeryCoWx]

You couldn’t pay me a lot of money to live in the Valley. Brutal down there.

Got through this tournament with a championship today and my oldest walked it off in extras so that made the 110s beat indices more tolerable!

[captainbarbossa19]

I will try to push this rain here in Starkville down to Southeast Texas. Lots of thunderstorms here this evening and it seems like it has been raining almost every day the past week.

[user:null]

I will try to push this rain here in Starkville down to Southeast Texas. Lots of thunderstorms here this evening and it seems like it has been raining almost every day the past week.

The best chance to make it work is later this week starting Wednesday.

[user:null]

Apparently, Philly once had a heat index of 129°F. Melbourne in FL had a 144°F heat index, the day they recorded the 90°F+ dewpoints.

[redneckweather]

You couldn’t pay me a lot of money to live in the Valley. Brutal down there.

Got through this tournament with a championship today and my oldest walked it off in extras so that made the 110s beat indices more tolerable!

Awesome! I remember those days very well when my son played travel ball with the Banditos for years. One of the hottest tournaments I can remember was in Fort Meyers. Absolutely brutal 5 day tournament but our team went undefeated and won the whole damn thing. Some argue it was the best Banditos team ever assembled and there have been some great ones.
It would get into the 90's during the day, high humidity and no breeze. A storm would come through, move along, the sun would come back out and it was like a sauna.
Here is my boy back when he was 18. He is on this board so just wanted to say thank you for the awesome memories all those years son (from 9 yrs old on into college)...Go Hard or Go Home!

[user:null]

Does anyone else notice how the GFS runs tend to create lots of these "specks,heterogenities, etc" within overall longwave patterns? Both the EMCWF and CMC models have them at times as well, but they both overall tend to be a lot "smoother" with the ridges and troughs compared to the GFS.

[DoctorMu]

I don't know what is going on in early July on GFS, but I like it.



Back door front?

[Stratton20]

July looks like it could * Potentially * be a wet month here, we will see

[JuneEl]

Is there any chance that Bret will affect our weather in the coming days?

[Stratton20]

JuneEl no, or at least it is very very unlikely to, bret will get ripped apart in the Caribbean graveyard

[Ptarmigan]

Is there any chance that Bret will affect our weather in the coming days?

Too early to say.

[Pas_Bon]

I don't know what is going on in early July on GFS, but I like it.



Back door front?

This would be a God-send. I always knew blue was my favorite color for a reason.