Skip to content
NTMS Propagation Path calculator

Path Calculator

Point-to-point prediction over HRRR profiles, SRTM terrain and ITU-R P.676 / P.530.

31.6, -98.4 · EM01sn · 8.0 ft AGL

33.1, -96.6 · EM13qc · 60.0 ft AGL
A callsign resolves through QRZ's mailing address, then geocoding — the position may be off from where the station actually operates.
Band
Station

Path calculation complete.

HRRR 08:00z · 9/9 path points
Distance
243.1
km · 151.1 mi
Bearing
44.2°
true · rev 224.2°
Terrain
BLOCKED
135.3 dB diffraction
Propagation
63/100
MARGINAL
Margin
-96.2
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 volume580 m AGL at the midpoint (1740 m above the chord, 870 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 27.6 m) clears with margin. The geometric line of sight is obstructed — buried 802 m below terrain at its worst point.

Great circle
31.565, -98.435 → 33.12, -96.615 · 44.2°
Loss budget · 24 GHz
FSPL (free-space) 167.8 dB
Gaseous (O₂ + H₂O) 11.1 dB
Diffraction 135.3 dB
Rain attenuation 0.0 dB
Total path loss 314.2 dB
Gas rate 0.0458 dB/km · H₂O 0.0020 dB/km/g · O₂ 0.0200 dB/km
Path abs. humidity avg 12.9 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 -314.2 dB
RX antenna gain 30.0 dBi
RX power -236.2 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -96.2 dB
Path weather · HRRR average of 9 samples
Temperature
71.6 °F
22.0 °C
Dewpoint
59.8 °F
15.5 °C
T/Td gap
11.7 °F
6.5 °C
Abs. humidity
12.9
g/m³
Pressure
957.0
mb
PWAT
22.6
mm
BL depth
210.3
m AGL
Refrac. gradient
-138.7
N/km · super-refractive
Propagation factors · 24 GHz 63/100
Rain
100 14%
Humidity
5 13%
PWAT
60 11%
Season
47 11%
T-Td Depression
60 10%
Refractivity
72 10%
Pressure
88 10%
Sky Cover
50 8%
Wind
50 8%
Time of Day
55 4%
Atmospheric profile HRRR 3 km Valid 2026-05-15 08:00 UTC · 9 samples
Point Lat, lon Temp Dewpt Press dN/dh BL m PWAT Duct
Source 31.6, -98.4 19.9 °C 15.9 °C 957.0 mb -126.9 167.1 20.2 mm
13% 31.8, -98.2 20.3 °C 16.0 °C 967.3 mb -138.7 153.4 20.4 mm
25% 32.0, -98.0 20.4 °C 15.6 °C 971.7 mb -94.2 69.8 23.5 mm
38% 32.1, -97.8 20.9 °C 15.8 °C 975.1 mb -91.3 165.2 22.7 mm
Midpoint 32.3, -97.5 22.4 °C 14.1 °C 979.8 mb -113.3 234.3 23.7 mm
63% 32.5, -97.3 22.7 °C 14.8 °C 983.7 mb -119.6 232.5 23.2 mm
75% 32.7, -97.1 23.6 °C 14.8 °C 989.2 mb -76.8 268.6 23.5 mm
88% 32.9, -96.8 23.7 °C 16.1 °C 993.0 mb -80.7 335.5 24.5 mm
Destination 33.1, -96.6 24.1 °C 16.0 °C 987.4 mb -91.5 266.6 22.0 mm
Midpoint vertical profile
18-hour forecast · this path · 24 GHz → steady
Propagation score for this path over the next 18 hours. 0 25 50 75 100
Peak 63 at 08:00 UTC · low 55 at 01:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
08:00 63 MARGINAL
09:00 61 MARGINAL
10:00 61 MARGINAL
11:00 62 MARGINAL
12:00 63 MARGINAL
13:00 62 MARGINAL
14:00 62 MARGINAL
15:00 62 MARGINAL
16:00 61 MARGINAL
17:00 62 MARGINAL
18:00 62 MARGINAL
19:00 61 MARGINAL
20:00 59 MARGINAL
21:00 59 MARGINAL
22:00 59 MARGINAL
23:00 60 MARGINAL
00:00 60 MARGINAL
01:00 · now 55 MARGINAL