Live/Radar/Every radar/KHDC
Single radar / Louisiana
Hammond radar KHDC
The weather service radar at Hammond, Louisiana, alone: each picture it makes from its own scans, at four tilts from its lowest up, every few minutes. Reflectivity, velocity, storm relative velocity, correlation coefficient and differential reflectivity, the storms it tracks and where they are headed, and how high its beam passes. How to read them.
- Latest scan
- Scanning
- Precipitation mode, pattern 212
- Tilts
- 0.5°, 1.3°, 2.4°, 3.1°
- Stands at
- 30.520°N 90.407°W, 141 ft above sea level
- Reaches
- 286 mi with reflectivity, 186 mi with velocity, 143 mi with storm relative velocity
Storms it tracks
The radar follows each storm cell from scan to scan, measures the way it is moving, and puts it ahead 15 to 60 minutes. Each is drawn on the map above, its track to the hour ahead marked each quarter hour.
| Storm | Where | Moving | In 30 minutes | In 60 minutes | Last forecast off by |
|---|---|---|---|---|---|
| G5 | 3 mi east southeast of Theodore, AL135 mi from the radar, bearing 89° | Toward the southeast at 7 mph | 6 mi east southeast of Theodore, AL | 9 mi southeast of Theodore, AL | 0.2 mi |
| O5 | 161 mi east southeast of the radar161 mi from the radar, bearing 120° | Toward the east at 6 mph | 163 mi east southeast of the radar | 166 mi east southeast of the radar | 0.8 mi |
| Q5 | 123 mi southeast of the radar123 mi from the radar, bearing 142° | Toward the south southeast at 15 mph | 130 mi southeast of the radar | 137 mi southeast of the radar | 0.5 mi |
| L5 | 6 mi north northeast of Slaughter, LA45 mi from the radar, bearing 295° | Toward the east southeast at 17 mph | 9 mi south southeast of Clinton, LA | 28 mi west northwest of the radar | 0.2 mi |
| R5 | 3 mi north of Ossun, LA101 mi from the radar, bearing 263° | Toward the south southeast at 45 mph | - | - | 3.1 mi |
| J5 | 5 mi south southeast of Crowley, LA117 mi from the radar, bearing 258° | Toward the east at 21 mph | 3 mi northwest of Maurice, LA | - | 1 mi |
| N5 | 154 mi southeast of the radar154 mi from the radar, bearing 125° | Toward the northeast at 39 mph | 159 mi east southeast of the radar | 167 mi east southeast of the radar | 0.7 mi |
| S5 | 6 mi north of Summit, MS59 mi from the radar, bearing 357° | First seen this scan | - | - | 0 mi |
How high it sees
The beam leaves the radar tilted up and the earth curves away under it, so the farther from the radar, the higher it passes. Rain or snow falling under the lowest beam is not seen: far from the radar, shallow snow and drizzle can fall unseen. The heights are the standard ones, the air bending the beam as the weather service’s own rule takes it.
| Tilt | 25 mi | 50 mi | 100 mi | 150 mi | 200 mi |
|---|---|---|---|---|---|
| 0.5° | 1,500 ft | 3,600 ft | 9,600 ft | 18,200 ft | 29,200 ft |
| 1.3° | 3,300 ft | 7,200 ft | 17,000 ft | 29,300 ft | 44,000 ft |
| 2.4° | 5,800 ft | 12,300 ft | 27,200 ft | 44,500 ft | 64,400 ft |
| 3.1° | 7,500 ft | 15,600 ft | 33,600 ft | 54,200 ft | 77,400 ft |
| Width | 2,200 ft | 4,400 ft | 8,800 ft | 13,100 ft | 17,500 ft |
How to read the pictures
- Reflectivity
- How strongly rain, snow and hail send the pulse back, in dBZ: the stronger, the heavier.
- Velocity
- The wind along the beam, in mph: green toward the radar, red away. Where the two meet tightly, the wind turns.
- Storm relative velocity
- The same wind with the storms’ own motion taken away, so a storm’s turning stands out: a tight pair of green and red is a rotating storm.
- Correlation coefficient
- How alike the returns of one pulse are, 0 to 1: rain and snow near 1, hail and melting snow lower, and debris a tornado lifts well below 0.8.
- Differential reflectivity
- How much wider than tall what falls is, in dB: large flat raindrops read high, hail and dry snow near 0.
Each picture is one tilt of one scan, as the radar sent it: its lowest tilt first, then three above it, the angles its scan pattern sets. A picture at a higher tilt sees higher into a storm, and farther over the ground at each distance. Press a point on the map to read the value there.
As data: /radar/now.json?show=sref&site=KHDC, the times of its frames, and /radar/s/KHDC/storms.json, the storms it tracks.