June 8, 2026 Monday Tropical Update
Boris and Cristina in Eastern Pacific bringing heavy rain to the Mexico and Central America coasts
June 2026 was the 18th-warmest June in the 132-year national record (1895–2026), at 70.6°F against a 1991–2020 normal of 69.5°F (+1.2°F).
June 2026 was the 32nd-wettest June in the 132-year national record (1895–2026), at 3.3in against a 1991–2020 normal of 3.1in (+0.2in).
NOAA/NCEI Climate at a Glance, contiguous United States. This is the observed record for the month, not a score of anything said in this piece — the forecast ledger begins 2026-08-17 and cannot reach earlier posts.
Scattered showers and storms this afternoon and evening along and east of the Mississippi River … heavy rain main threat without organized severe weather.
Gulf of Mexico has some scattered storms along the coast from Texas to the Florida panhandle but nothing tropical brewing in situ. However, the remnants of Tropical Storm Cristina (03E) in the Eastern Pacific off the coast of Nicaragua may cross into the Bay of Campeche and spin something up there down the road toward weekend.
Eastern Pacific + Central American Gyre | Precipitable Water Next 6-days
Tropical Storms Boris and Cristina will be in close proximity to land — and won’t have a chance to intensify very much beyond a minimal Tropical Storm. However, the heavy tropical moisture will lead to potential flooding in Mexico and Honduras.
Cyclonic Vorticity Next 6-days … to track the atmospheric circulation (spin) of the tropical systems. Cristina does likely cross from EPAC to Gulf of Mexico, but unlikely to still be a named system (or a tropical depression) but could still maintain enough of a lower level circulation to be a “crossover event” and not need a new name.
Tropical Weather Headlines for Monday
Atlantic: Medium-range (5-7 days) low chance in the southern Gulf of Mexico (Bay of Campeche) with Cristina crossing Central America within deep layer moisture plume (Central American Gyre Circulation) … any system would be quite weak. Previous ensemble output from last week was a false alarm.
Eastern Pacific: Tropical Storm Boris (02E) is near the southern coast of Mexico and will make landfall on Tuesday. Newly formed Tropical Storm Cristina will drift along the coat of Nicaragua and Honduras into Wednesday. Its circulation or remints should cross into the southern Bay of Campeche by weekend. Main threat is heavy rain.
Western Pacific: no activity expected in next 7 days, surprisingly quiet out there.
ECMWF Flagship Ensemble Cyclone Tracks (12z)
Into next weekend, watching the southern Gulf of Mexico for low chance (<20%) of TS/Hurricane activity out of a large circulation/ gyre centered over Mexico + Central America with input from remnants of Tropical Storm Cristina (03E).
Flagship model: ECMWF HRES 12z —> Integrated Vapor Transport next 10-days
The large scale flow with the Central American Gyre picks up the remnants of an Eastern Pacific tropical system into the southern Gulf (Bay of Campech) … and then the very strong Caribbean —> Gulf of Mexico moisture plume resumes around the westward extension of the Bermuda High. We’ll be watching this [typical] pattern for the next 2-weeks, at least.
ECMWF 12z | Precipitable Water | My Favorite Parameter
Moisture continues to surge due northward through the central Lower 48 into southern Canada. Heavy rain is primary threat from this very moist air mass with daytime heating. A strong trough / cool front blasts through the Midwest and Great Lakes into the weekend = dry and cooler.
ECMWF 12z | Precipitation Type + MSLP | Next 6-days
Current Temperatures | RTMA | 6:00 PM ET
Current Temperature Anomaly | RTMA | 6:00 PM ET
Lower 48 was +1.9°F above normal
High Temperatures Next 8-Days —> Wednesday June 17th.
Heat wave coming for mid-Atlantic and Northeast with 90s for 2-3 days before the Canadian cool front sweeps through the Lower 48 … quite impressively cool for mid-June in the Midwest and Great Lakes —> also no one is complaining.
Low Temperatures Tuesday Morning
60s and 70s billowing up in the Great Lakes but only 50s in the Northeast.
High Temperatures on Monday
95 million at least 90°F … and 289 million at least 80°F.
10-day Forecasts from Blend of Models for a few cities
Minneapolis and Chicago with a nice string of days of perfect weather in the 70s
Upper-Level Height Anomaly | AIFS-Single Next 10-days
Strong mid-level trough swings into the Midwest and Great Lakes by late in week and then intensifies — cooler pattern (!) across Central Lower 48 into mid-June.
ECMWF Flagship Ensemble Mean Temperature Anomaly next 15-days
Week 1 —> June 8 to June 14
Week 2 —> June 15 to June 21
Significantly below normal for the middle of the Lower 48 … 6°F to 8°F cooler than typical mid-June temperatures
HRRR PWAT + Radar Simulation Next 48-Hours —> Wed 2 PM ET
Weather Pattern into Tuesday Morning
Weather Pattern on Tuesday
NWS Precipitation Next 72-hours —> Thursday Afternoon
Blend of Models —> Precipitation Next 10-days
Atlantic Basin Satellite Channels | IR Channel 13 + Water Vapor
Entire basin is very quiet with any tropical waves showing limited convection. Very little convection in the Gulf of Mexico — or elsewhere in the Atlantic basin.
NASA Dust Forecast Next 10-days
African dust layers might be significant — as usual — but they contain very little dust compared to previous years.
North Atlantic Tropics | Quiet Next 7-days
4 Tropical Waves — none developing in the Atlantic, but as they eventually reach the Eastern Pacific, could trigger formation, as we see with Boris and Cristina
Strong Trade Winds but nothing spinning in the Caribbean or the main Atlantic basin
My favorite parameter —> Precipitable Water (PWAT) next 10-days
Tropical storms and hurricanes are bundles of high moisture air > 2” in the column (or more) so we look for areas of concentrated high PWAT air in the tropics —> and we also can view frontal boundaries or dry air input from the middle-latitudes into the subtropics or tropics + Saharan Air Layers (dry)
Integrated Vapor Transport —> IVT next 12-days from ECMWF AIFS
Eastern Pacific is busy with Boris (02E) and Cristina (03E) along Mexico/Central America within the gyre. However, their proximity to land will limit development.
The deep layer moisture plume surges through the Caribbean into the Gulf and then northward through eastern U.S. — and we will still be watching for any tropical cyclone development in the southern Gulf in the next several days.
Eastern Pacific Tropics | 2026 Season
2026 Names —> Amanda, Boris, Cristina, Douglas, Elida
Tropical Storm Boris (02E)
Disorganized — 45 mph winds landfall on Tuesday.
Tropical Storm Cristina (03E)
May reach 50-60 mph winds by Wednesday with landfall into early Thursday.
Main threat is heavy rain —> Total Precipitation Next 6-days
Western Pacific Basin — Typhoon Season — Quiet next 7-days+
Global Ocean Temperatures —> Sea Surface Temperature (SST)
Tropical storms need at least 26°C SST to form and intensify … and hurricanes most often become major with 28°C SST (at least).
There are still rather cool (relative) areas in the Western Pacific and North Atlantic compared to the growing warmth along the Equator and off the western coast of Mexico with the oncoming El Niño. The recent 20-year climatology highlights much better than an older 1991-2020 baseline.
Atlantic Ocean Temperatures | SST Analysis (June 9 00z)
The Atlantic remains cooler than past 2-decades across the Main Development Region [MDR] from the Lesser Antilles (Caribbean) to the Canary Islands and coast of Africa. The North Atlantic off the East Coast and into the mid-latitudes is also quite cool.
Thank you for reaching the end of this post! Hopefully you enjoyed the tour of the global tropics and what’s coming in the weeks/months ahead in the tropics here on Weather Trader on Substack.
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For 2026 Hurricane Season: Every 6 or 12 hours, we get an update including these model output
ECMWF EPS full-physics ensembles … 50 perturbed members + control/HRES
ECMWF AIFS-Ensemble (data driven) … another 50 members + control
ECMWF AIFS-Single … a special deterministic system that has exceptional skill
NOAA GEFSv12 Ensembles … 30 perturbed members + control
NOAA GFSv16 … 13-km high resolution global deterministic
UK Met Office MOGREPS lagged ensembles … global 14-km 72-members per day
Environment Canada ensembles + Germany ICON + Australia BOM Unified Model
New Google WeatherNext 1000-member ensemble system (!) more on that in future post
My Atlantic Hurricane Season Forecast (2026)
From April 7, 2026: Atlantic Seasonal Hurricane Forecast: (11/5/2)
9-13 Named Storms (11 most likely)
4-7 Hurricanes (5 or 6 most likely)
1-3 Major Hurricanes (2 most likely)
Accumulated Cyclone Energy: 75-85 (well below normal)
NOAA 2026 Atlantic Hurricane Season Forecast
More details in Thursday, May 21, 2026 Tropical Update
The Intertropical Convergence Zone (ITCZ) in the tropics along 5°N to 10°N is where moist air can ascend and form thunderstorms or like a convective pot boiling over = convection. In the coming weeks, especially into late June, we’ll look for areas of disturbed weather — which means persistent convection — and potential formation of low pressure swirls along the ITCZ with tropical waves, in the Caribbean and Gulf of Mexico (America) with decaying frontal boundaries, and other pathways like tropical transition or subtropical cut-off lows. Lots of options/ways to form a tropical storm in the Atlantic in any given season.
The Bermuda High —> Azores High in the subtropics usually keeps things quiet in the latitude around 30°N and suppresses the ITCZ to the south in late May into June. On the periphery of the Bermuda High, moisture plumes out of the Caribbean into the Gulf and then Texas + Southeast.
- Milepost
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