The Inside on the Outside
The Big Picture WPC · 4:00 AM EDT today
Hurricane Lala has strengthened again, and for the first time this week, real watches are up: the Papahanaumokuakea Marine National Monument now sits under a Hurricane Watch and a Tropical Storm Watch as Lala turns toward it. On the mainland, the ingredients are aligning for a corrected, sharpened severe-weather threat from northeast Kansas into central Missouri today, with flash flooding tracking a parallel course through the Midwest. The heat wave gripping the South is set to loosen its grip there over the coming week even as it tightens over the Southwest — a handoff CPC’s own numbers now spell out in detail.
Lead Story: Watches Are Up for Lala CPHC/NHC Advisory No. 25 · 5:00 AM HST today
Hurricane Lala — 85 mph, Watches Posted HURRICANE WATCH ISSUED
Lala has strengthened to 85 mph, and this is the first advisory of the week with real watches attached: a Hurricane Watch now covers the Papahanaumokuakea Marine National Monument from Lisianski Island to Maro Reef, with a Tropical Storm Watch extending from Maro Reef east to French Frigate Shoals. The storm is centered about 390 miles southeast of Maro Reef, moving west near 9 mph, with a turn toward the west-northwest and northwest forecast tonight and Wednesday, then north on Thursday — the turn that carries it into the watch area. Forecasters expect additional strengthening over the next day or so, with hurricane conditions possible in the watch area by Thursday and tropical storm conditions possible as early as Wednesday night. Large surf will reach the Monument’s low-lying atolls beginning Wednesday, likely inundating some of them, especially from French Frigate Shoals to Maro Reef.
Trouble Spots
Severe Storms — Northeast Kansas Into Central Missouri SLIGHT RISK (CORRECTED)
SPC issued a correction to today’s outlook to fix the orientation of the wind-threat line — worth knowing because it means this forecast has already had a second, closer look. Thunderstorms with severe wind gusts and isolated large hail are expected this afternoon and evening from the central Plains into the lower Missouri Valley, as a lingering outflow boundary from an earlier storm complex interacts with an approaching cold front and a heat-driven surface low over western Kansas. The more confident scenario sits farther east across eastern Kansas, where storms are expected to cluster quickly this evening and grow upscale into a forward-moving complex pushing into Missouri — damaging gusts becoming the main threat once that happens. Isolated severe gusts and hail are also possible from the northern Rockies into the central High Plains and eastward into the Midwest and southern Lower Michigan, with damaging gusts also possible across Mississippi and Alabama.
Flash Flooding — Midwest to Missouri Valley SLIGHT RISK
Two zones again today. Around the western Great Lakes — the Chicago-to-Milwaukee corridor — a shortwave riding the cold front’s leading edge should spark thunderstorms this afternoon and evening; the latest high-resolution guidance puts 20-35 percent odds on two-plus inches of rain along I-94/I-80, with soils in the corridor still worn down from a rough recent stretch. Farther southwest, a more potent disturbance digging out of the northern Rockies is expected to fire up thunderstorms late this afternoon across eastern Nebraska into northern Missouri and Kansas, with solid model agreement on 1-2 inches of rain, locally higher, as the same system feeds tonight’s severe threat.
Severe Storms — Wednesday: Ozarks Into the Lower Ohio Valley SLIGHT RISK
The system reloads Wednesday. SPC’s Day 2 outlook has a Slight Risk from southern Missouri into northern Arkansas and across southern Illinois and far western Kentucky/Tennessee, with the greatest risk sliding from the Ozarks into the Lower Ohio Valley Wednesday afternoon and evening — isolated strong to severe storms capable of hail and strong to severe wind gusts, with the boundary’s position still carrying some uncertainty.
Dangerous Heat — South, Southeast & Building Into the Southwest EXTREME HEAT WARNINGS
The ridge parked over the South and Southeast keeps producing record highs and record-warm overnight lows. Extreme Heat Warnings and Heat Advisories stretch from Dallas/Fort Worth and Oklahoma City east to the Southeast coast, with overnight lows in the low 80s in spots denying any real recovery. By Wednesday, ridging strengthens over the Southwest, bringing record-challenging warmth there too. Check on neighbors and family without reliable air conditioning.
Fire Weather — Columbia Basin/Snake River & Southern Plains ELEVATED
SPC’s Day 1 outlook flags an Elevated area across the Columbia Basin and adjacent Snake River Plain in Washington and Idaho, where westerly winds of 10-15 mph and afternoon relative humidity near 15 percent will develop in the lee of the Cascades. A second Elevated area sits over the southern Plains — the Texas Panhandle into western Oklahoma — where a drought-stressed fuel environment, temperatures near 100°F, and relative humidity down to 10-15 percent keep the risk in place. Day 2 shows no Critical areas, but the same drought-stressed pattern continues over the Desert Southwest.
The Tropics — Three Basins NHC/CPHC outlooks · this morning
Central & East Pacific: Lala Leads, and CPC Sees Company Coming
Lala leads (see above). Behind her, the eastern Pacific has two more candidates in the pipeline: a low expected to form several hundred miles south of southern Mexico around week’s end, with high (80 percent) odds of developing within seven days but expected to stay well offshore; and a tropical wave southwest of Baja California, already producing disorganized showers, given medium (60 percent) odds of organizing and tracking westward into the central Pacific behind Lala. CPC’s own extended outlook backs this up independently — its forecasters expect a tropical cyclone to form in the East Pacific by next weekend, and specifically tie above-normal rain and temperature odds for Hawaii to a system that may develop southeast of the islands.
Atlantic: As Quiet as the Bulletin Allows
Tropical cyclone formation is not expected in the Atlantic, Caribbean, or Gulf during the next seven days — about as quiet a statement as the National Hurricane Center can issue. No waves are currently flagged with development potential. Two oceans, two entirely different stories.
The Inside what the discussions actually say
The reasoning behind the forecast, pulled from the technical discussions forecasters write for each other.
A “CORR” is forecasters showing their work. Today’s SPC Day 1 outlook carries a rare tag: “CORRECTED FOR WIND CIG1 LINE ORIENTATION.” That’s not a sign of a shaky forecast — it’s SPC catching and fixing the shape of its own wind-threat line before the public even had time to act on the wrong version. When you see “CORR” on a product, the forecast reasoning underneath hasn’t changed; only the map got sharper.
Two watches, one turn. Lala’s watches didn’t appear because the storm got closer in a straight line — they appeared because forecasters gained confidence in a turn. The storm has been heading almost due west for days; what changed today is confidence that it curves west-northwest, then northwest, then north by Thursday, carrying it directly into the Monument. Watches follow the turn, not just the distance.
The heat handoff, now with numbers attached. CPC’s 6-10 day outlook (valid Aug 23-27) puts better than 60 percent odds on above-normal heat for the Rockies, Central-to-Southern Plains, and Southeast, with the strongest signal — above 80 percent — over the southern Plains. But it also shows a moderate trough building over the eastern Great Lakes and Northeast, tilting those areas toward near-normal or even below-normal. That’s the same “heat relocates” pattern WPC’s extended discussion described, just now with confidence numbers instead of just direction.
Space weather’s quiet subplot. SWPC’s forecast discussion notes the geomagnetic field has been sitting at quiet-to-G1 (Minor storm) levels, driven by leftover effects from an August 14th coronal mass ejection colliding with the onset of a negative-polarity coronal hole high-speed stream. Forecasters expect unsettled-to-active conditions through August 20th, with G1 storm periods likely August 19th as that high-speed stream’s influence grows — worth a glance north after dark the next couple of nights.
Looking Ahead CPC · 3:00 PM EDT Mon — current issuance
For August 23-27: the pattern is dominated by an amplified ridge parking over the Great Plains, with 500-hPa heights holding near 596 dm through the period. That supports above-normal temperature odds exceeding 60 percent across the Rockies, Central-to-Southern Plains, and parts of the Southeast, maxing out above 80 percent over the southern Plains. Precipitation confidence is lower, but the same ridge favors below-normal rainfall across the southern Plains, Lower Mississippi Valley, and parts of the Southeast, while a moderate trough over the eastern Great Lakes and Northeast tilts those areas toward near-normal-to-below-normal temperatures and a slight lean toward above-normal precipitation. For Hawaii, above-normal precipitation and temperatures (better than 70 percent odds) are tied to the potential tropical system CPC expects to develop southeast of the islands this week.
Also Watching
- Aurora Watch: Geomagnetic field sitting at quiet-to-G1 (Minor storm) levels on leftover CME effects; G1 storm periods likely August 19 as a negative-polarity coronal hole high-speed stream takes over. Worth a look north the next couple of nights if you’re in the northern tier. SWPC · 12:30 UTC today
- Fire Weather: Elevated risk today for the Columbia Basin/Snake River Plain (WA/ID) and the southern Plains (TX Panhandle/OK); no Critical areas. Same drought-stressed pattern continues into the Desert Southwest Wednesday. SPC Fire Wx · this morning
- Drought Monitor: Weekly product; the next national map lands Thursday, August 20 — featured here every Thursday issue.
One Cool Thing
Notice the shift in Lala’s own advisory language today: “the core forecast” isn’t just tracking a position anymore, it’s tracking a turn — and that turn is why a stretch of ocean most people have never heard of just got its first hurricane watch of the season. The Papahanaumokuakea Marine National Monument is larger than every U.S. national park combined, and almost entirely uninhabited; the “residents” under that watch are mostly seabirds, monk seals, and a handful of researchers.
Shareables
Source Ledger every claim, timed & sourced
Our standard: nothing in this briefing older than 8 hours without a flag. Products that update once daily or weekly are used at their most recent issuance and marked. This issue is the first sourced entirely through the automated Drive pipeline — no products required pasting or live web-fetching.
| Product | Issued | Status |
|---|---|---|
| WPC Short-Range Forecast Discussion | 4:00 AM EDT Tue Aug 18 | CURRENT |
| WPC Extended (Day 3-7) Discussion | 3:16 AM EDT Tue Aug 18 | CURRENT |
| WPC Excessive Rainfall Discussion | 3:59 AM EDT Tue Aug 18 | CURRENT |
| SPC Day 1 Convective Outlook (CORR 1) | 9:10 AM CDT Tue Aug 18 | CURRENT |
| SPC Day 2 Convective Outlook | 12:46 AM CDT Tue Aug 18 | CURRENT |
| SPC Day 3 Convective Outlook | 2:27 AM CDT Tue Aug 18 | CURRENT |
| SPC Day 1 & Day 2 Fire Weather Outlooks | 10:29 AM / 12:28 AM CDT Tue Aug 18 | CURRENT |
| NHC Atlantic Tropical Weather Outlook | 8:00 AM EDT Tue Aug 18 | CURRENT |
| NHC East Pacific Tropical Weather Outlook | 5:00 AM PDT Tue Aug 18 | CURRENT |
| CPHC Central Pacific Tropical Weather Outlook | 2:00 AM HST Tue Aug 18 | CURRENT |
| Hurricane Lala Advisory No. 25 (Public/Forecast/Discussion) | 5:00 AM HST Tue Aug 18 | CURRENT |
| CPC 6-10/8-14 Day Prognostic Discussion | 3:00 PM EDT Mon Aug 17 | CURRENT ISSUANCE · daily product; next ~3 PM today |
| SWPC Forecast Discussion | 12:30 UTC (8:30 AM EDT) Tue Aug 18 | CURRENT |
For Newsrooms & Reporters
Need a Meteorologist On Air or On the Record Today?
Bob Cox — veteran broadcast meteorologist heard mornings on WTIC NewsTalk 1080 (Hartford) and forensic meteorologist with 30+ years analyzing high-impact weather — tracks these stories in real time and is available for interviews and expert comment: radio, TV, print, podcast, fast turnaround.
Today’s interview-ready angles: Hurricane Lala’s first watches of the week and what a Hurricane Watch over an uninhabited national monument actually means · the corrected Plains severe weather threat and the Kansas City-Missouri corridor · CPC’s numbers on the Southeast-to-Southwest heat handoff · a possible G1 geomagnetic storm and aurora chances Wednesday night.
BOOKING: kaitlin@coxweatherservices.com · 888-248-9347 · coxweatherservices.com · attribution: “Bob Cox, meteorologist, Cox Weather Services”