DOCTRINE, SOURCES & SYSTEM METHODOLOGY
The United States Army Tactical Weather Decision Support System is an autonomous environmental telemetry and decision-aid pipeline designed to provide commanders, staff officers, and tactical operations centers (TOCs) with real-time operational risk evaluations across 43 major military installations and combat commands worldwide.
By continuously fusing numerical numerical weather predictions (NWP) from Open-Meteo with authoritative live METAR surface observations from the NOAA Aviation Weather Center (AWC), the system systematically applies United States Army doctrine thresholds to generate composite GO, CAUTION, and NO-GO postures across three core mission domains: Aviation / Rotorcraft, Ground Maneuver / Trafficability, and Dismounted Infantry / Thermal Stress.
Battlefield Weather Effects
Governs weather tactical decision aids (WTDAs), rotary/fixed-wing aircraft limits, crosswind tolerances, and soil trafficability proxies.
- Aviation Wind Limits: Sustained winds & gusts ≥ 35 kts constitute a mandatory NO-GO (structural and control authority threshold). Gusts between 25–34 kts require CAUTION (external sling loads prohibited, severe low-level turbulence).
- Flight Minimums: Evaluated against FAA / Military flight categories. Low Instrument Flight Rules (LIFR: ceiling < 500 ft or visibility < 1.0 SM) generates a mandatory NO-GO. IFR / MVFR requires CAUTION.
- Soil Trafficability: Evaluates precipitation intensity and antecedent moisture. Current rain > 10 mm/hr or 24h accumulation ≥ 25 mm triggers NO-GO due to catastrophic loss of mobility in off-road maneuver.
- Optics Obscuration: Visibility < 1.0 km triggers Ground NO-GO due to loss of thermal sight acquisition range and convoy restrictions (< 10 mph).
Heat Injury Prevention
Prescribes operational controls for Wet Bulb Globe Temperature (WBGT) and Apparent Heat Index categories to prevent exertional heat illness.
| Heat Flag | WBGT / Heat Index | Work / Rest | Posture |
|---|---|---|---|
| Cat 1 (White) | 78.0 – 81.9°F (25.6–27.7°C) | Continuous | GO |
| Cat 2 (Green) | 82.0 – 84.9°F (27.8–29.3°C) | 50 / 10 min | GO |
| Cat 3 (Yellow) | 85.0 – 87.9°F (29.4–31.0°C) | 40 / 20 min | CAUTION |
| Cat 4 (Red) | 88.0 – 89.9°F (31.1–32.1°C) | 20 / 40 min | CAUTION |
| Cat 5 (Black) | ≥ 90.0°F (≥ 32.2°C) | 10 / 50 min | NO-GO |
Cold Injury Prevention
Defines hypothermia prevention, cold-wet weather discipline, and wind chill frostbite exposure thresholds.
- Cold-Wet Caution (≤ 32°F / 0°C): Hypothermia hazard accelerated by dampness, rain, or wet footwear. Enforces frequent sock changes, vapor-barrier boot inspections, and warm beverage cycles. Status: CAUTION.
- Severe Wind Chill Hazard (≤ 0°F / -18°C): Exposed flesh at risk of frostbite in under 30 minutes. Mandatory rotational warming shelters, buddy-check enforcement, and curtailment of non-essential exposed operations. Status: NO-GO.
- Freezing Rain / Glaze: Immediate NO-GO for all dismounted foot columns and unpaved convoys due to severe traction hazard and rapid hypothermia induction.
Hourly Cron Cadence (MM:02)
Execution wrapper runs at 2 minutes past each hour (24 runs/day) to synchronize freshly issued METARs and hourly NWP model cycles.
NOAA AWC METAR API Ingestion
Authoritative METAR JSON queried for all CONUS/OCONUS military airfields (e.g., KGRK, KHOP, KPOB, ETIC, RODN). Extracts exact runway flight categories, ceiling base AGL, altimeter, and visibility in statute miles.
Open-Meteo High-Resolution NWP
Batched global numerical queries extract 7-day daily high/low projections, hourly precipitation probability, solar radiation, soil temperature, and moisture trafficability proxies.
Order of Battle (OOB) Enrichment
Static lookup from installations_oob.json merges tenant units, host commands, and primary combat platforms (e.g., AH-64E, M1A2 SEPv3, HIMARS) into each observation.
Doctrinal Rule Engine & Posture Rollup
Holistic evaluation determines limiting triggers ("Why"), cell alert highlights, dual timestamps (UTC/Zulu + Local), and automated staleness warnings (> 60 min).
The dashboard calculates an overall operational posture based on the conservative "Worst-Case Limiting Factor" principle:
Triggered if ANY single branch (Aviation, Ground, or Dismounted) evaluates to NO-GO. Direct mission hazard requiring operational mitigation or commander risk acceptance.
Triggered if at least one branch evaluates to CAUTION and no branch is NO-GO. Indicates degraded operational capabilities (e.g. sling load halts, reduced convoy speed, heat work/rest cycles).
Triggered when ALL three branches are within favorable green parameters. Unrestricted tactical operations authorized under normal safety postures.