Super Typhoon Champi (Rosal) is Category 5 over the Philippine Sea, about 1,270 km east of Central Luzon, moving west-northwest. Sustained winds near 195 km/h, gusts to 240. Signal No. 1 is up over parts of northern Luzon. Not a direct hit on main Philippine islands. RainViewer forecast takes it near northern Taiwan then into southeast China later this week, with the track reaching areas near Guangzhou and Shenzhen. Heavy rain and strong winds possible for northern Taiwan and coastal China Friday–Saturday. Check PAGASA, CWA Taiwan, and China Meteorological Administration before travel plans.

Istanbul saw extreme rain: northern districts 190–270 mm in 24h (Beykoz up to 273 mm). Among the highest since 1985 and roughly one-third of the annual average in places. Warm Black Sea waters, cold Balkan air and moist northerly flow drove it. At least three deaths, widespread flooding, road collapses and flight diversions. Rain continues into Friday with more showers possible through the weekend. Saturated ground raises flood risk. Avoid low-lying areas and unnecessary travel. Wishing everyone in Istanbul well. İstanbul’daki herkese geçmiş olsun.

Remnants of Tropical Storm Rachel recently dropped 1.08 inches on Las Vegas, tying the all-time October daily record from 1947. That is roughly a quarter of the city’s 4.2-inch annual average (NOAA normals). October normally sees only ~0.32 inches. Radar cores hit 48 dBZ over the Strip and valley, filling washes and closing roads. Desert pavement turns modest totals into flash floods fast. (📸casinocompwallet, 🌦️RainViewer)

Hurricane or typhoon? Same storm, different ocean. Nolo just crossed the Date Line as a hurricane and became a typhoon, the first since Dora in 2023. Now it's spinning alongside Typhoon Choi-wan and TS Koguma: the West Pacific's first October trio in 5 years😮

Tokyo has been wet for 35 days in a row, the longest streak since records began in 1886. Rain has fallen every day this September, a first. By this morning September was already at more than 690 mm, three times normal, beating the 1958 record. A stalled front and typhoons kept feeding the rain. JMA sees a possible break from Thursday night, after Typhoon Surigae passes the Izu Islands. お気をつけて。東京も早く乾きますように。

Rain from Thursday night into Friday night! Bangkok, 25 Sep. Heavy spells, then a lighter tail. RainViewer: downpour-strength echoes over the capital. Up to about 190 mm in 24 hours in the east of the city. Roads flooded, traffic jammed, bikes stalled. Saen Saep overflowed onto Lat Phrao and Ramkhamhaeng. Canal-side homes at risk. More heavy rain through the weekend. Eases next week. Check radar before you go. ระวังน้ำท่วมขังนะ ตรวจเรดาร์ก่อนออกเดินทาง ขอให้ทุกคนปลอดภัยและโชคดี

Wednesday update on storm Polo. Unusually fast jump: 45 mph Monday, Category 5 Tuesday. About 110 mph in 24 hours. Peak 180 mph, 892 mb. 2nd-lowest eastern Pacific pressure after Patricia. NHC: 155 mph Cat 4, 300 km S of Zihuatanejo. Closest today-Thursday. Core is forecast offshore. Follow the storm path in RainViewer. Official warnings: NHC / SMN. Sigue la trayectoria de la tormenta en RainViewer. Para avisos oficiales, consulta al SMN.

Polo is a new 45 mph storm south of Manzanillo. The surprising part: winds could more than double in two days and reach major-hurricane strength. Watch from Tecpan de Galeana to Punta San Telmo. Heavy rain and rough surf first. The center should stay off Colima. RainViewer shows Category 4 Thursday. Check NHC / SMN before travel. También en la costa: vigilancia de Tecpan de Galeana a Punta San Telmo. Sigue al SMN.

A new Pacific tropical storm got a name today: Dujuan (24W), east of the Marianas. The name comes only at 34 knots. Japan is on its second named storm in a week. Closest look 19–20 Sep near Izu and Kanto. Tokyo, Chiba, and Shizuoka sit on the edge of the cone. Follow it in RainViewer. Confirm with JMA and JTWC. #台風25号

Your Apple Watch just got smarter about rain 📷️ The new RainViewer watch face shows live radar - not just a temperature icon. See rain moving in real time, plus up to 2 forecast frames (+15min, +30min), right on your wrist. Update to RainViewer to unlock it. Free for everyone.

Tropical Depression Krovanh is turning toward southern Japan. About 30 kt, near 31.2N 132.8E, moving north then northeast. The center is forecast to skirt Shikoku and Kansai tonight into Wednesday, then turn extratropical. Tokyo stays off the center track but still sees rain as Krovanh feeds a stalled front. Check JMA warnings before travel. If you are on iOS and want to join the Rain Viewer beta, TestFlight is open: testflight.apple.com/join/7w…

Hurricane Lowell is turning toward Hawaiʻi. Category 3 (~120 mph), about 500 miles south of Kauaʻi, moving north. The center is forecast to pass west of Kauaʻi late Monday night into Tuesday. Not a direct hit on Honolulu. Kauaʻi is under a Hurricane Watch and Tropical Storm Warning. Expect heavy rain, flash flooding, and dangerous surf. Check NHC / NWS Honolulu before travel or beach plans.

Help us test RainViewer for iOS We’ve opened a public TestFlight for RainViewer on iOS. Invite: testflight.apple.com/join/… Your criticism is very welcome, so please don’t hold back. Small details matter, especially the ones that make the app feel slower, less clear, or less intuitive than it should. If something feels off, tell us. Radar lag, a clunky control, a widget that doesn’t match the map, confusing behavior, awkward UX. We want to hear about it all. Honest feedback is how RainViewer gets more polished, reliable, and actually nicer to use. How to report: * Send feedback through TestFlight, or * Email [email protected] with Public TestFlight in the subject line, so it doesn’t mix with App Store tickets. Include device, iOS version, and what you expected vs what happened. Thanks for helping us make RainViewer better 🤘🏼

Edouard hit the TX-LA line Tuesday as a 60 mph / 95 km/h tropical storm. On Wednesday it dumped 10-21 in / 250-530 mm across East Texas. Trees smashed roofs, a school stadium wall came down, cars and homes flooded, and crews pulled people from the water. Power took a beating too: about 80k outages at the peak, with tens of thousands still dark as flooding slowed repairs. Thursday the remnants sit near Tyler. A bit more rain is possible in the first half of the day, then it should fade. Flood watches remain. Watch live radar.

A composite radar map refreshes every 2 minutes and resolves rain down to 125 meters. A forecast refreshes a few times a day. Neither is "better" - they answer different questions. RainViewer's founder breaks down why treating radar as just a live version of the forecast is a mistake most weather (and travel) apps make: hackernoon.com/how-radar-dat…

Pacific is unusually active. Seven tropical cyclones are currently tracked across the North Pacific: Typhoon Saudel, Tropical Storm Narra, Tropical Depression Atsani, Tropical Storm Lala, Tropical Depression Moke, Tropical Storm Iselle and Tropical Depression Ten-E. This concentration of simultaneous systems is uncommon. The last comparable cluster across the basin occurred in 2017. The primary driver is a strengthening El Niño. It has raised sea surface temperatures and reduced vertical wind shear over large portions of the Pacific, creating highly favorable conditions for genesis and persistence. Notable local effects: Narra has brought heavy rain, floods and landslides to northern Vietnam. Saudel is enhancing monsoon rains over the Philippines. Moke keeps a flash-flood risk for Hawaii’s Big Island. Iselle may briefly reach hurricane strength, with rough surf for Baja. Ten-E is expected to be absorbed by Iselle soon.

Weekend vibes activated. Heavy metal lightning⚡️🎸 (@mikkedkx)

We got a review that made us curious: “total rubbish your better off with a lump of seaweed outside your back door” Fair enough. Coverage isn’t perfect everywhere. But what really stuck with us was the seaweed part. Why would anyone hang seaweed outside the back door, and how does it relate to a weather app? It turns out this isn’t just an awkward idiom. It’s real weather forecasting history. For centuries along the British and Irish coasts, people really did hang a piece of seaweed outside the door as a simple weather forecast. If it stayed dry and stiff, fair weather was on the way. If it went soft and damp, rain was coming. Seaweed absorbs moisture from the air, so it worked as a basic natural humidity sensor. Sometimes the history of meteorology is more interesting than one would expect🫰

Hurricane Lala passed roughly 30 miles offshore of Hawaiʻi Island, sparing a direct hit but still triggering a flash flood emergency on Oʻahu and widespread power outages across the islands. It's now pulling away northwest, weaker for now - but NHC/CPHC gives it a real chance of re-strengthening back to hurricane status by Tuesday or Wednesday. Near-miss track, real impacts anyway. Photo Credit: RainViewer /bloginyahawaii