NOAA Weather Radio and Satellite Reception

NOAA Weather Radio (NWR)

NOAA Weather Radio (NWR) is a nationwide network of radio stations broadcasting weather forecasts, watches, warnings, and emergency alerts 24 hours a day. It is the "voice of the National Weather Service."

NWR Frequencies

• 162.400 MHz
• 162.425 MHz
• 162.450 MHz
• 162.475 MHz
• 162.500 MHz
• 162.525 MHz
• 162.550 MHz

SAME: Precise Alerting

Specific Area Message Encoding allows NWR receivers to filter alerts by county. Instead of hearing alerts for the entire state, SAME-enabled radios only activate for your specified counties.

Types of Alerts

• Tornadoes, severe thunderstorms, flash floods
• Hurricanes and tropical storms
• Winter storms, blizzards, ice
• Amber Alerts
• Civil Emergency Messages
• 911 Telephone outages

The End of the POES/APT Era (2025)

Critical update: The POES (Polar Operational Environmental Satellites) constellation was officially decommissioned in 2025. NOAA-18 was decommissioned on June 6, 2025, following transmitter failure. NOAA-19 was decommissioned on August 13, 2025, following battery-cell failure. NOAA-15 — the last satellite still transmitting APT (Automatic Picture Transmission) — was decommissioned on August 19, 2025, concluding 47 years of continuous POES operations.

This means the analog APT system that amateur and hobbyist receivers had used since the 1960s is no longer active on any satellite. The frequencies previously used for NOAA APT reception (137.620 MHz for NOAA-15, 137.9125 MHz for NOAA-18, 137.100 MHz for NOAA-19) are now silent.

Current Polar Weather Satellites: Meteor-M2-3

The primary source of polar-orbiting weather satellite imagery accessible to hobbyists is now Russia's Meteor-M2-3, launched June 27, 2023. It operates in a sun-synchronous polar orbit at approximately 820 km altitude, with a 101-minute orbital period and 98.6° inclination.

Meteor-M2-3 carries the LRPT (Low Rate Picture Transmission) system — a digital QPSK signal at 72 ksymbol/s on VHF. Unlike the old analog APT, LRPT provides approximately 1 km resolution(compared to APT's 4 km) and transmits multiple spectral channels. However, the satellite experienced an antenna deployment issue after launch, resulting in reduced signal strength.

Meteor-M2-3 Satellite Details

• NORAD Catalog Number: 57166
• International Designator: 2023-091A
• Perigee / Apogee: 815 km / 822 km
• Inclination: 98.6°
• Orbital Period: 101.1 minutes
• LRPT Downlink: 137.100 MHz (primary) and 137.900 MHz (secondary) — both transmit identical LRPT data
• HRPT: 1,700 MHz (full resolution, requires larger antenna)

Current TLEs (July 2026)

Meteor-M2-4 (NORAD 59051):

1 59051U 24039A   26206.59011976  .00000003  00000-0  21125-4 0  9990 2 59051  98.7040 165.4103 0008143  62.8932 297.3076 14.22433001124726

Meteor-M2-3 (NORAD 57166):

1 57166U 23091A   26206.60216221  .00000001  00000-0  19219-4 0  9993 2 57166  98.6067 260.7897 0004983  66.8954 293.2750 14.24049561159980

LRPT: Receiving Digital Weather Satellite Imagery

LRPT (Low Rate Picture Transmission) is the digital successor to APT. It uses QPSK modulation at 72 ksymbol/s, transmitting compressed image data and sensor data from the AVHRR instrument. The signal occupies approximately 80 kHz of bandwidth. Both 137.100 MHz (primary) and 137.900 MHz (secondary) transmit identical LRPT data — tune to whichever is clearer in your location.

The AVHRR sensor on Meteor-M2-3 and M2-4 images in multiple channels including visible, near-infrared, and thermal infrared. The LRPT signal transmits these at approximately 62 kbps after Reed-Solomon error correction, convolution encoding, and interleaving. The effective radiated power is approximately 2–6 watts (3.2–8.0 dBW EIRP).

Equipment for LRPT Reception

• RTL-SDR dongle (RTL2832U-based, v3 or v4 recommended) — provides 2.56 MHz bandwidth, sufficient for the 80 kHz LRPT signal
• 137 MHz antenna — a QFH (quadrifilar helix) or turnstile antenna tuned to 137.9 MHz; omnidirectional and circularly polarized, ideal for satellite reception. The QFH provides superior circular polarization for satellite signals.
• SDR software — SDR++ or SDR# for receiving and demodulating the QPSK signal
• LRPT decoder — SatDump 1.2.2 or newer nightly build (actively maintained, cross-platform) is the recommended decoder; it handles QPSK demodulation, frame synchronization, deinterleaving, Reed-Solomon decoding, JPEG decompression, and image rendering

LRPT Reception Step by Step

• Step 1: Check pass predictions using Heavens-Above, N2YO, or SatDump's built-in predictor. Meteor-M2-3 and M2-4 pass overhead approximately 2–4 times daily at mid-latitudes
• Step 2: Point your QFH or turnstile antenna straight up with clear sky view — these antennas are omnidirectional so precise pointing is not critical
• Step 3: Tune SDR++ to 137.900 MHz (or 137.100 MHz) in FM (NFM) mode with approximately 80 kHz bandwidth. Set gain to auto or manually adjust for clean reception
• Step 4: Route audio from SDR++ to SatDump via a virtual audio cable (Windows: VB-Audio Cable, macOS: BlackHole, Linux: PulseAudio/pipewire)
• Step 5: In SatDump, select the Meteor LRPT plugin and initiate demodulation. As the satellite passes, you will see the QPSK constellation lock and image strips appear
• Step 6: After the pass, SatDump can apply map overlays and color enhancement to the decoded channel data

Active Polar Weather Satellites (July 2026)

GOES Geostationary Weather Satellites

Geostationary satellites provide continuous full-disk imagery of Earth — no waiting for polar-orbiting satellite passes. NOAA operates two GOES-R series satellites:

• GOES-18 — positioned at 75.2°W, serving as GOES-East. Became operational July 2022 after replacing GOES-17. Carries the Advanced Baseline Imager (ABI) for 16-channel multispectral imaging.
• GOES-17 — positioned at 137.2°W as GOES-West. However, its ABI cooler has experienced thermal issues since 2018, causing degraded performance for some infrared channels during certain orbital positions.

GOES LRIT/HRIT Reception

GOES satellites transmit data via LRIT (Low Rate Information Transmission)at 1686.6 MHz (L-band). LRIT carries processed imagery, sounding data, and text products at approximately 64–128 kbps. This signal can be received with a small dish antenna and appropriate LNB.

• Dish: 60–120 cm parabolic dish pointed at GOES-East (75.2°W) or GOES-West (137.2°W)
• LNB: Specialized L-band LNB tuned to 1686.6 MHz; modified FTA (Free-To-Air) LNBs can work with external filtering
• Software: GOES-R GLT Tool (NOAA freeware), SatDump (supports GOES LRIT), or dedicated GOES image viewers
• Full-disk images of the Americas are received continuously, updated every 10–15 minutes

GOES Satellite Reference

Satellite Pass Prediction

Predicting satellite passes is essential for polar-orbiting satellites (Meteor) but unnecessary for geostationary satellites (GOES), which appear stationary.

Prediction Tools

• SatDump — built-in satellite predictor, directly usable for pass planning and LRPT decoding workflow
• Heavens-Above — enter your location to see Meteor-M2-3 passes with ground track maps and elevation charts
• N2YO — real-time tracking and 10-day pass predictions for all satellites
• Stellarium — desktop planetarium with satellite tracking plugin

What to Look For

• Maximum elevation: Passes above 30° give the best signal quality; above 60° is ideal
• Duration: Overhead passes last 10–15 minutes; low passes 5–8 minutes
• Doppler correction: At 137.9 MHz with a 820 km satellite, Doppler shift is approximately ±3.5 kHz — most SDR software handles this automatically
• Daylight passes: Visible channel imagery requires sunlight; infrared channels work day and night
• TLE freshness: Update Two-Line Element data every few days from Celestrak or Space-Track for accurate predictions