Live/Radar/Every radar/KLWX
Single radar / Virginia
Sterling radar KLWX
The weather service radar at Sterling, Virginia, 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
- 38.976°N 77.487°W, 290 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 |
|---|---|---|---|---|---|
| R9 | 110 mi north northeast of the radar111 mi from the radar, bearing 13° | Toward the northeast at 37 mph | 124 mi north northeast of the radar | - | 2.1 mi |
| F8 | 145 mi north northeast of the radar145 mi from the radar, bearing 20° | Toward the northeast at 33 mph | 160 mi north northeast of the radar | - | 1.3 mi |
| J2 | 92 mi north northwest of the radar92 mi from the radar, bearing 348° | Toward the north northeast at 38 mph | - | - | 2.2 mi |
| X9 | 13 mi west northwest of Frostburg, MD104 mi from the radar, bearing 302° | Toward the north at 28 mph | 109 mi northwest of the radar | - | 2.1 mi |
| X0 | 135 mi north northeast of the radar135 mi from the radar, bearing 14° | First seen this scan | - | - | 0 mi |
| U9 | 108 mi north northwest of the radar108 mi from the radar, bearing 335° | Toward the north northeast at 43 mph | 122 mi north northwest of the radar | 138 mi north of the radar | 1 mi |
| C9 | 90 mi northwest of the radar90 mi from the radar, bearing 323° | Toward the northeast at 45 mph | 98 mi north northwest of the radar | - | 1.2 mi |
| K9 | 107 mi north northeast of the radar107 mi from the radar, bearing 25° | Toward the northeast at 30 mph | 122 mi north northeast of the radar | 137 mi north northeast of the radar | 0.6 mi |
| Z0 | 116 mi northwest of the radar116 mi from the radar, bearing 315° | First seen this scan | - | - | 0 mi |
| S7 | 6 mi northwest of Westernport, MD96 mi from the radar, bearing 295° | Toward the north at 16 mph | - | - | 3.1 mi |
| F0 | 123 mi northwest of the radar123 mi from the radar, bearing 308° | Toward the northwest at 30 mph | - | - | 2.6 mi |
| Q7 | 2 mi east southeast of Enon, VA115 mi from the radar, bearing 175° | Toward the north northeast at 35 mph | 8 mi east of Sandston, VA | 5 mi east of Central Garage, VA | 0.2 mi |
| E8 | 11 mi north of Cumberland, MD89 mi from the radar, bearing 311° | Toward the northeast at 48 mph | 93 mi northwest of the radar | 104 mi north northwest of the radar | 0.5 mi |
| T5 | 71 mi north northwest of the radar71 mi from the radar, bearing 345° | Toward the northeast at 37 mph | 82 mi north of the radar | 94 mi north of the radar | 0.9 mi |
| S9 | 69 mi northwest of the radar69 mi from the radar, bearing 312° | First seen this scan | - | - | 0 mi |
| V0 | 3 mi west northwest of Bull Run, VA8 mi from the radar, bearing 194° | First seen this scan | - | - | 0 mi |
| D1 | 3 mi northwest of Cresaptown, MD86 mi from the radar, bearing 302° | First seen this scan | - | - | 0 mi |
| Z7 | 2 mi southwest of Robinwood, MD45 mi from the radar, bearing 345° | Toward the north northeast at 29 mph | 6 mi northwest of Highfield-Cascade, MD | - | 1.2 mi |
| G0 | 3 mi southwest of Tuckahoe, VA98 mi from the radar, bearing 184° | Toward the northeast at 45 mph | 8 mi northeast of Ashland, VA | - | 1.3 mi |
| B0 | 11 mi north northwest of Brightwood, VA50 mi from the radar, bearing 235° | Toward the northeast at 3 mph | - | - | 2.3 mi |
| X8 | 3 mi southwest of Fredericksburg, VA48 mi from the radar, bearing 182° | Toward the northeast at 29 mph | 4 mi southeast of Aquia Harbour, VA | At Indian Head, MD | 0.7 mi |
| I0 | 2 mi south southwest of Meadowbrook, VA108 mi from the radar, bearing 180° | Toward the north northeast at 18 mph | At Richmond, VA | - | 1 mi |
| C1 | 4 mi north northeast of Fountainhead-Orchard Hills, MD54 mi from the radar, bearing 348° | First seen this scan | - | - | 0 mi |
| Y9 | 4 mi south southeast of Buckhall, VA21 mi from the radar, bearing 172° | Toward the north northeast at 43 mph | At Great Falls Crossing, VA | At Damascus, MD | 0.7 mi |
| O9 | 98 mi north of the radar98 mi from the radar, bearing 2° | Toward the north northeast at 31 mph | - | - | 4.5 mi |
| F9 | 5 mi north of Massanutten, VA75 mi from the radar, bearing 243° | Toward the north northeast at 37 mph | 3 mi east southeast of Mount Jackson, VA | - | 1.5 mi |
| I1 | 10 mi west of Hancock, MD70 mi from the radar, bearing 318° | First seen this scan | - | - | 0 mi |
| T0 | 5 mi east northeast of Orange, VA56 mi from the radar, bearing 212° | First seen this scan | - | - | 0 mi |
| B4 | 5 mi east northeast of Lake Wilderness, VA45 mi from the radar, bearing 191° | Toward the north at 30 mph | 9 mi east of Bealeton, VA | At Linton Hall, VA | 0.9 mi |
| J1 | 5 mi south of Strasburg, VA46 mi from the radar, bearing 266° | First seen this scan | - | - | 0 mi |
| J8 | At Stanley, VA61 mi from the radar, bearing 244° | Toward the north northeast at 32 mph | 10 mi southeast of Woodstock, VA | 3 mi southeast of Middletown, VA | 0.3 mi |
| K6 | 6 mi north northwest of Lake of the Woods, VA41 mi from the radar, bearing 203° | Toward the north at 44 mph | 3 mi northeast of Warrenton, VA | - | 1.6 mi |
| E0 | 6 mi south southeast of Winchester, VA35 mi from the radar, bearing 286° | Toward the north northeast at 8 mph | 5 mi east southeast of Winchester, VA | - | 1 mi |
| Z9 | 9 mi south of Gordonsville, VA77 mi from the radar, bearing 210° | 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=KLWX, the times of its frames, and /radar/s/KLWX/storms.json, the storms it tracks.