Distance
203.8
km · 126.6 mi
Bearing
39.0°
true · rev 219.0°
Terrain
BLOCKED
117.8 dB diffraction
Propagation
68/100
GOOD
Margin
-59.8
dB over CW threshold
Terrain profile · SRTM 30 m + canopy + MS footprints
Line of sight
1st Fresnel
Duct layer
Horizon ray
Common volume
Over the horizon: the two horizon-skimming rays intersect at the common volume ≈ 407 m AGL at the midpoint (1222 m above the chord, 611 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 39.1 m) clears with margin. The geometric line of sight is obstructed — buried 572 m below terrain at its worst point.
Great circle
31.773, -97.831 → 33.189, -96.452 · 39.0°
Loss budget · 10 GHz
FSPL (free-space)
158.6
dB
Gaseous (O₂ + H₂O)
1.4
dB
Diffraction
117.8
dB
Rain attenuation
0.0
dB
Total path loss
277.8
dB
Gas rate 0.0070 dB/km · H₂O 0.0000 dB/km/g · O₂ 0.0070 dB/km
Path abs. humidity avg 7.0 g/m³
Power budget
TX power
20.0
dBm
(100.0 mW)
TX antenna gain
30.0
dBi
Feed loss (×2)
-2.0
dB
EIRP
48.0
dBm
Path loss
-277.8
dB
RX antenna gain
30.0
dBi
RX power
-199.8
dBm
Sensitivity (CW, 500 Hz)
-141.0
dBm
Margin
-59.8
dB
Path weather · HRRR average of 9 samples
Temperature
80.1 °F
26.7 °C
Dewpoint
43.6 °F
6.4 °C
T/Td gap
36.5 °F
20.3 °C
Abs. humidity
7.0
g/m³
Pressure
977.0
mb
PWAT
13.7
mm
BL depth
2221.4
m AGL
Refrac. gradient
0
N/km
Propagation factors · 10 GHz
68/100
Rain
100
14%
Humidity
70
13%
PWAT
75
11%
Season
68
11%
T-Td Depression
55
10%
Refractivity
50
10%
Pressure
88
10%
Sky Cover
50
8%
Wind
50
8%
Time of Day
18
4%
Atmospheric profile
HRRR 3 km
Valid 2026-05-03 20:00 UTC
· 9 samples
Point
Lat, lon
Temp
Dewpt
Press
dN/dh
BL m
PWAT
Duct
Source
31.8, -97.8
24.5 °C
7.2 °C
977.0 mb
1981.0
12.8 mm
—
13%
31.9, -97.7
25.8 °C
7.5 °C
991.0 mb
2098.3
14.6 mm
—
25%
32.1, -97.5
26.3 °C
8.1 °C
997.0 mb
2132.5
14.4 mm
—
38%
32.3, -97.3
26.4 °C
6.3 °C
991.7 mb
2123.7
12.7 mm
—
Midpoint
32.5, -97.1
26.4 °C
6.2 °C
995.8 mb
2290.9
12.1 mm
—
63%
32.7, -97.0
27.8 °C
5.4 °C
998.2 mb
2291.4
12.6 mm
—
75%
32.8, -96.8
28.6 °C
4.4 °C
998.6 mb
2409.0
14.4 mm
—
88%
33.0, -96.6
26.9 °C
8.9 °C
997.3 mb
2285.5
16.9 mm
—
Destination
33.2, -96.5
27.8 °C
4.1 °C
995.4 mb
2379.9
13.3 mm
—
Midpoint vertical profile
17-hour forecast · this path · 10 GHz
→ steady
Peak 82
at 05:00 UTC
· low 65
at 22:00 UTC
| Hour UTC | Score | Rating |
|---|---|---|
| 20:00 | 72 | GOOD |
| 21:00 | 74 | GOOD |
| 22:00 | 65 | GOOD |
| 23:00 | 71 | GOOD |
| 00:00 | 66 | GOOD |
| 01:00 | 76 | GOOD |
| 02:00 | 68 | GOOD |
| 03:00 | 79 | GOOD |
| 04:00 | 71 | GOOD |
| 05:00 | 82 | EXCELLENT |
| 06:00 | 72 | GOOD |
| 07:00 | 75 | GOOD |
| 08:00 | 81 | EXCELLENT |
| 09:00 | 79 | GOOD |
| 10:00 | 79 | GOOD |
| 11:00 | 72 | GOOD |
| 12:00 · now | 74 | GOOD |