Which frontier roads could close in the next 72 hours, where, and why.
Hourly levels for rain-triggered landslides, snow, ice, fog and thunderstorms at 70 points on eight public highways: Siliguri to Gangtok and Nathu La, over Sela to Tawang, across Zoji La to Leh, from Manali over Baralacha La, through Banihal to Srinagar, up the Alaknanda to Badrinath, and from Shillong to Silchar. Official NDMA alerts for the same districts sit alongside. For BRO, state public works departments, district administrations and transport planners.
Mountain roads on the frontier carry civilians, transporters and the forces on the same narrow strip, and weather closes them. Between 30 June and 4 September 2026, 267 people died in disaster-related incidents in Himachal Pradesh, 159 of them in road accidents, and landslides had 92 roads blocked on 5 September (Rozana Spokesman, citing the State Emergency Operations Centre for the road count). On 22 January 2026, ten soldiers died when an Army truck skidded off the Bhaderwah to Chamba road at about 9,000 ft (All India Radio).
The information exists, but in pieces: IMD and SACHET warn by district, BRO and the PWDs announce closures bulletin by bulletin, DGRE issues avalanche bulletins and GSI landslide forecasts for a few districts. Nobody joins them up per road, per hour, ahead of time.
- A 72-hour board for eight corridors: the worst level in each 6 hours, Normal Watch Warning Danger, with the place and hour it starts and the reason in plain words.
- Hour-by-hour grids for every point on a road: rain against a published landslide threshold, fresh snow at road level, the 0 °C level against the road profile, ice, visibility, gusts and thunderstorm energy.
- Official NDMA SACHET alerts for the districts each road crosses, shown exactly as issued, with the reason each was matched.
- A closure log kept in the operator's browser: closures and reopenings copied from official bulletins, exported as CSV or JSON for the record.
- A published method: every formula, threshold and source, and what the levels cannot tell you.
- Pick the points70 public places on the roads: towns, passes, a lake, tunnel portals. Checked against OpenStreetMap routing and the Copernicus DEM.
- Read the weatherOne batched Open-Meteo request: 10 days back for antecedent rain, 72 hours ahead, temperature at road height.
- Apply the rulesRain against the Dahal and Hasegawa (2008) Himalayan threshold; snow from the 0 °C level; ice; IMD fog bands; CAPE; a capped avalanche watch.
- Add official alertsSACHET CAP messages for the nine states, matched to roads by district code, district, place or region.
- PublishBoard, corridor pages, closure log and methods. Every number carries its source and time; a failed fetch keeps the last good export.
The full method, with formulas, thresholds, sources and known failure modes, is in the methods note and, with live retrieval times and the point checks, on the console's methods page.
| Source | What | Licence | Status |
|---|---|---|---|
| Open-Meteo Forecast API | Hourly rain, snowfall, snow depth, 0 °C level, temperature, visibility, gusts, CAPE, weather code; 10 days back, 4 ahead | CC BY 4.0 | Live |
| NDMA SACHET (CAP) | Official alerts: all-India and nine state feeds, each recent CAP message | Official public warnings | Live |
| OpenStreetMap via OSRM | Road lines, road km of each point | ODbL | Refreshed on demand |
| Copernicus DEM GLO-90 | Point elevations and road profiles | Copernicus DEM licence | Refreshed on demand |
| GSI landslide forecasts | District forecasts for 24 and 48 hours (Darjeeling, Kalimpong, Rudraprayag operational) | Government of India | Read via SACHET when issued |
| DGRE avalanche bulletins | Daily danger levels by district in winter | Government of India | Wanted |
| BRO and PWD road status | Official closures and openings | Government of India | Wanted: logged by hand today |
Nothing in MARGA is simulated. There is no public machine-readable feed of BRO or PWD road status today, so closures are copied into the closure log from bulletins.
- BRO task forces and project offices: which stretches need clearing crews and plant positioned in the next three days.
- State PWDs and NHIDCL: where slides, snow and ice are likely on the highways they maintain.
- District administrations and disaster management authorities: when to issue advisories, hold traffic or open relief points, next to the official alerts already in force.
- Transport planners and permit offices: which days to avoid on high passes, from public road and weather data only.
- Advisory only. Every page names the agencies whose status and warnings come first.
- Public roads and public places only. No military positions, and never convoy timings or movements.
- The closure log stays in the operator's browser, refuses convoy and troop movement wording, phone numbers and email addresses, and deletes entries after 180 days.
- Official alerts are shown unchanged; MARGA only says which roads they concern and why.
- Every number shows its source and time; an outlook older than 12 hours is flagged on every page.
- The thresholds are heuristics and have not been calibrated against closures or slides on these roads; that needs a season of logged closures.
- Rain and snow come from weather models with cells several kilometres wide; cloudbursts and short downpours are underestimated.
- The landslide threshold was fitted in Nepal on rain gauges; local thresholds differ, and slides also follow road cutting, drainage, snowmelt and earthquakes.
- Ice uses air temperature, fog uses model visibility, and the avalanche watch ignores slope and snowpack. DGRE and GSI bulletins come first.
- The free Open-Meteo API is for non-commercial use. A deployment needs a subscription or a self-hosted copy.
Pilot with one BRO project or one district: add your stretches and known slide zones as points, log a season of closures, and we calibrate the thresholds against them. contact@trinetra.in