WEATHERAmerica Newsletter, Saturday, November 29, 2025; WEATHER EXTREMES And GLOBAL SATELLITE IMAGERY

[Larry Cosgrove]

WEATHER HAZARDS (During The Next 24 Hours)

 

SEVERE WEATHER OUTLOOK
(potential for tornadoes, damaging winds, and large hail within the next 24 hours)

 

Some Thunderstorms May APPROACH Severe Limits

NY....CT....RI....MA....VT....NH....ME....QC Eastern Townships

Some Thunderstorms May APPROACH Severe Limits

SE LA....S MS....S AL....FL Panhandle....GA

ISOLATED Severe Thunderstorms

(Microbursts, Large Hail, Isolated Tornadoes)

AZ....W NM....W CO....E UT

 

HEAVY RAINFALL OUTLOOK
(potential for an inch or more total rainfall within the next 24 hours)

 

Isolated Locations In

NY....CT....RI....MA....VT....NH....ME....QC Eastern Townships

(QPF 1 - 2")

Isolated Locations In

AZ....W NM....W CO....E UT

(QPF 1 - 2")

 

WINTER WEATHER POTENTIAL

(potential for Moderate Icing, Snow 2 - 4" or more, and/or temperatures below 10 deg F)

 

Isolated Locations In

QC....E ON

(Snow; 4 - 12")

Isolated Locations In

N MB....N ON....W QC

(Intense Cold)

Scattered Locations In

AZ....W NM....W, C CO....E UT....W WY

(Snow; 4 - 16"; Mostly Above 4000 Feet)

GLOBAL WEATHER SUMMARY

(a review of important weather features around the world)

 

IODC

ECMWF; METEOBLUE; EUMETSAT

 

Looking wetter and more wintry. Gradually.

With three 500MB shortwaves forecast to move through southwestern Asia within the next ten days, opportunities for colder air and precipitation will be increasing. But most of the numerical models are reticent in terms of higher water amounts and snowfall production, as most of the cAk vortex will stay over Siberia. Every time an impulse in the polar westerlies undercuts the gyre, usually on a track from North Africa to northern Iran and Afghanistan. colder values will be pulled south into the Levant, Persia and Indus River watershed. We will need to see southward advance/progression of the snowpack line, which may get into the Zagros Range and western/northern Pakistan by the third week in December. In between disturbances and cold fronts, pleasantly mild/warm temperatures will be found below 35 N Latitude.

 

HIMAWARI 8

METEOBLUE; Kochi University

 

There is a ton of misinformation about the position and strength of the Madden-Julian Oscillation being tossed around in discussions both professional and amateur. Let me summarize by saying that the MJO is incoherent and mainly pulsing in Phase 3. The convective belts are feeding subtropical jet streams on both sides of the Equator, but are also showing a linkage to the northern branch and could start to feed the powerful large cyclones across the northern Pacific Basin. Those Wheeler diagram forecasts and wind anomaly band predictions are of no help whatsoever , while the convective outlooks in the subtropics certainly are.. We are not locked into a pattern in North America, but the Eurasian temperature pattern will produce some incredible cold above 40 N Latitude, which may also be the case in parts of western and eastern Canada.

Tropical moisture is targeting northern and central Australia, as well as New Zealand and New Caledonia with heavy thunderstorms; summer weather alignments are starting to show. Very hot air will expand out of the southern and eastern portion of the Australian subcontinent.

 

GOES WEST

NOAA/NESDIS

 

If you think that the satellite image resembles something of a cross between an El Nino and a La Nina weather landscape, you would be correct. An impressive subtropical jet stream from the equatorial Pacific Basin carries two strong impulses toward Mexico, and is even reflected in another fetch through Panama and Colombia. Meanwhile, two prominent cold vortices/storms in the Gulf of Alaska and below the Aleutian Islands will occasionally pump up atmospheric heights to produce transient blocking signatures in far northern Canada and Greenland. Those ridges may act in concert form the moderate +PNA anticyclone in the Great Basin to enable cold intrusions east of the Rocky Mountains.

And what if these two powerful jet streams phase? Oh just remember something that happened in the winter four and a half years ago. 

 

GOES EAST

NOAA/NESDIS

 

Arctic air, although somewhat more modified than what was predicted by earlier model guidance, has a firm grip on most of Canada and the northern half of the lower 48 states. The storm which has brought heavy snows across the Upper Midwest and Great Lakes region will head off to the St. Lawrence Valley on Sunday, and likely push the leading edge of the cA regime into portions of Texas and the Deep South. But ridging over the western states should maintain above normal temperatures there and in the High Plains/West Texas. This is a progressive pattern, even with positive 500MB height anomalies occasionally showing up in Greenland and Baffin Island. So the warmth to the left of the Interstate 35 corridor should reach the East Coast late next weekend.

Southern branch energy is bringing substantial rain and thunder to Central America and the Lesser Antilles. With a warming trend in play, orograohoc+diurnal convection is lining up inland on the windward side of the Andes Range In Chile and Argentina. See also the macro tropical wave centered over the Amazon Basin, and a frontal structure of colder origin in Argentina.  

 

METEOSAT

ECMWF; METEOBLUE; EUMETSAT

 

As seems to be the case in North America, tghe European subcontinent is enmeshed in an amplified, yet somewhat progressive, upper air pattern that is largely cool or cold with mostly scattered potential for frozen precipitation. The polar westerlies contain cold upper lows, while the southern branch is so low as to touch on the Equator over the Atlantic Ocean and central Africa. This type of configuration, should it continue, may bring very cold temperatures into play even in parts of the Mediterranean countries. Note the organized shortwave well to the southwest of the Canary Islands, a feature that is usually a good benchmark for colder values into the Atlas Mountains and even some points in the Sahara Desert.

Diurnal convection with hot and humid conditions are seen throughout the southern half of the African continent.