KJFK EGLL

John F Kennedy International Airport London Heathrow Airport
Route Information
Departure

KJFK (JFK)

Distance

5,539.7 km (2,991.2 nautical miles)

Arrival

EGLL (LHR)

Flight Time

440 minutes (7h 20m)

Flight Profile

Cruise Altitude: 39,000 ft (Flight Level 390)

Route calculated using great circle navigation

Turbulence Comfort Along Route Comfort View
Comfort Score: Combines turbulence probability (GTG forecast) with intensity (ZTI analysis). High scores indicate both high probability AND high intensity turbulence.
Smooth
Comfortable
Noticeable
Uncomfortable
Formula: (Probability × Intensity)
Flight Smoothness Score
8.5 /10
Smoothness
Smooth Flight
42%
Smooth
57%
Light
1%
Moderate
AI-Powered Flight Briefing
📊 11,000 data points analyzed
Advanced AI-Powered Flight Briefing
Your Flight

We analysed more than 11,000 data points along your route from John F Kennedy International Airport, New York to London Heathrow Airport, London.

Your Journey Beta

5 hours 35 minutes into the flight: Some moderate bumps expected.
The crew may adjust altitude or ask you to stay seated during these sections.
The rest of the flight should be smooth.

Your route takes you over the Appalachian Mountains and crossing the North Atlantic Ocean – these areas can sometimes cause light turbulence.

Smooth Flight

We're expecting smooth conditions throughout your flight. You can sit back and relax.

Takeoff

Takeoff should feel smooth with possible light bumps, with calm conditions around the airport.

Winds Aloft

Winds at cruising altitude are about 42 knots. These winds are favorable and may get you there up to 27 minutes early.

Landing

Landing should feel smooth with possible light bumps with typical approach conditions.

You're in Safe Hands

If you feel nervous at any point, remember that turbulence is expected, safe, and part of normal flying. The crew is monitoring everything, and the aircraft is built to handle far more than anything you will feel. Have a safe and calm flight.

Relaxation Exercises
Live data from ECMWF global forecast models • 12 atmospheric pressure levels analyzed • Updated every 6 hours
Most Common
LIGHT
57% of your flight
Peak Intensity
MODERATE
Brief sections only
Route Breakdown (112 zones)
Moderate
1 zones (1%)
Light
64 zones (57%)
Smooth
47 zones (42%)
Forecast Valid: Jun 01, 18:00 UTC (Generated: Jun 01, 18:00 UTC)
Flight Timeline 7h 20min
Maximum turbulence expected per segment
Takeoff
Light
0:30-1:00
Light
1:00-1:30
Smooth
1:30-2:00
Smooth
2:00-2:29
Light
2:29-2:58
Light
2:58-3:27
Light
3:27-3:56
Light
3:56-4:25
Light
4:25-4:54
Smooth
4:54-5:23
Smooth
5:23-5:52
Moderate
5:52-6:21
Light
6:21-6:50
Light
Landing
Light
Smooth
Light
Moderate
Severe
Longer bars indicate higher turbulence intensity. Values shown are the maximum for each time segment.
Turbulence Metrics ZTI and EDR
Comparing Two Turbulence Metrics:
  • ZTI (ZeroTurb Index): Our proprietary composite metric (0.0-1.0 scale)
  • EDR (Eddy Dissipation Rate): ICAO/WMO official standard (m^(2/3)/s scale)
ZTI Scale (Custom)
Smooth
<0.2
Light
0.2-0.5
Moderate
0.5-0.75
Severe
>0.75
EDR Scale (ICAO)
Smooth
<0.1
Light
0.1-0.4
Moderate
0.4-0.7
Severe
>0.7

Detailed Analysis Below: While flights generally follow these patterns, our advanced turbulence prediction system analyzes real-time weather data, atmospheric conditions, and pilot reports to provide you with precise, route-specific forecasts. Review the detailed metrics and interactive maps below for a comprehensive understanding of expected conditions along your flight path.

How Aircraft Size Affects Your Comfort

Did you know that the size of your aircraft can affect how turbulence feels? Larger, wide-body aircraft have more mass and inertia, which means they absorb turbulent air movements more smoothly. Smaller regional jets and turboprops are lighter, so passengers may feel more noticeable movement during the same turbulence conditions.

Important: All commercial aircraft, regardless of size, are designed and certified to safely handle even severe turbulence. The difference is only in passenger comfort - not safety.

Learn more about how aircraft size affects your turbulence experience
Technical Forecast Details Advanced Analysis

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Comprehensive Flight Profile Altitude • Wind • Turbulence

Flight Altitude Profile
  • X-axis: Distance along route (km)
  • Y-axis (left): Aircraft altitude (feet)
  • Blue = Climb phase
  • Green = Cruise phase
  • Orange = Descent phase
Pilot Reports (PIREPs)

Real turbulence reports from pilots who recently flew near your route:

  • Green = Smooth (no turbulence)
  • Yellow = Light turbulence
  • Orange = Moderate turbulence
  • Red = Severe turbulence
Wind Speed
  • Y-axis (right): Wind speed in knots
  • Sudden wind changes often indicate turbulence
  • Hover over points to see wind direction
AI Comfort Forecast
  • Y-axis (right): Comfort Score (0-70)
  • <1 = Smooth (cyan)
  • 1-25 = Light (green)
  • 25-50 = Moderate (orange)
  • >50 = Severe (red)
Tip: Look for areas where multiple indicators coincide (e.g., pilot reports + AI forecast + wind changes) to identify the most likely turbulence zones.
Aurora Status: Aurora forecast unavailable (Kp Index: 0)
Global Winds Forecast ECMWF Open Data Worldwide Coverage
Route-Specific Forecast: Wind data calculated at 112 waypoints along your flight path using high-resolution ECMWF global weather model (0.25° grid, ~25km resolution).
Minimum Winds
5 kt
6 mph
Average Winds
42 kt
49 mph
Maximum Winds
100 kt
116 mph
Valid: Jun 02, 00:00 UTC
Source: European Centre for Medium-Range Weather Forecasts
Flight Planning: Headwinds increase flight time and fuel consumption. Tailwinds decrease both. Strong crosswinds may affect takeoff/landing at airports.
Wind Impact Analysis GOOD
Wind Assessment: Favorable tailwinds (33 kt avg) provide good conditions for this flight. Light crosswinds averaging 22 kt - minimal impact
Route Wind Breakdown
Tailwinds
76 zones (68%)
Crosswinds
35 zones (31%)
Moderate tailwinds averaging 33 kt - good conditions for this route
Flight Time Impact
33 kt
Avg Tailwind
-27 min
Time Impact
Faster than normal ✓
Wind Range:
• Max Tailwind: 90 kt
• Max Headwind: 0 kt
• Max Crosswind: 90 kt
Wind Speed Along Route ECMWF Forecast
ZeroTurb Index (ZTI) Analysis Custom Algorithm
What is ZTI? Our proprietary ZeroTurb Index combines three meteorological indicators to give you a comprehensive turbulence probability (0.0-1.0 scale). The chart below shows how each component contributes to the overall ZTI along your route:
  • Richardson Number (Ri): Atmospheric stability - lower values indicate CAT risk
  • Wind Shear Index (WSI): Rate of wind speed/direction changes
  • Temperature Gradient Index (TGI): Frontal boundary strength
  • ZTI (Composite): Proprietary composite of the three indices above
ZTI Thresholds: Smooth: 0.0-0.2 Light: 0.2-0.5 Moderate: 0.5-0.75 Severe: 0.75-1.0
Scientific GTG Analysis NOAA Standards
For Aviation Professionals: This section shows turbulence zones using conservative NOAA GTG thresholds. These scientific thresholds are more cautious than the user-friendly "Comfort View" above, which better represents typical passenger experience.

Note: Modern aircraft are designed to handle moderate turbulence effortlessly. What scientific models classify as "moderate" often goes unnoticed by passengers due to advanced flight control systems and aircraft structural design. Most commercial flights encounter some level of atmospheric turbulence that the aircraft manages automatically.
Zone Distribution (Scientific Thresholds)
27%
Smooth (<15%)
30 zones
11%
Light (15-30%)
12 zones
61%
Moderate (30-50%)
68 zones
2%
Severe (≥50% prob)
2 zones
Threshold Comparison
Category Comfort View Scientific (NOAA)
Smooth <20% probability <15% probability
Light 20-50% 15-30%
Moderate 50-75% 30-50%
Severe ≥75% ≥50%
Turbulence Probability Along Route GTG Forecast
Low (0-30%)
Light or no turbulence
Medium (30-50%)
Moderate turbulence likely
High (50-70%)
Moderate-severe expected
Extreme (70-100%)
Severe turbulence
Active Turbulence Warnings (AIRSIGMETs) Loading...
Winds Forecast FL390
Departure (KJFK)
300°
NW
81 kt
93 mph
-55°C / -67°F
En Route Average
300°
NW
81 kt
93 mph
-55°C / -67°F
Arrival (EGLL)
300°
NW
81 kt
93 mph
-55°C / -67°F
Forecast Valid: Jun 02, 00:00 UTC (Issued: Jun 01, 18:00 UTC)
Flight Level 390 (39,000 ft)
Reading Wind Arrows: Arrow points in the direction the wind is blowing FROM. Example: Arrow pointing up (0°) = North wind blowing from North to South.
Pilot Reports (PIREPs) - 32 Reports
What are PIREPs? Pilot Reports (PIREPs) are real-time observations from pilots flying the route. They provide the most accurate turbulence information available.
Time (UTC) Intensity Altitude Aircraft Report
Airport Forecasts (TAF) - Next 24-30 Hours
Departure: KJFK
Valid: Jun 01 20:00 - Jun 03 00:00 UTC
20:00 - 23:00 UTC
Wind: 110° at 14 kt gusting to 24 kt
Visibility: 6+ SM
Clouds: SCT 7000 ft
FM 23:00 - 05:00 UTC
Wind: 100° at 9 kt
Visibility: 6+ SM
Clouds: FEW 7000 ft
FM 05:00 - 13:00 UTC
Visibility: 6+ SM
Clouds: FEW 25000 ft
FM 13:00 - 17:00 UTC
Wind: 350° at 8 kt
Visibility: 6+ SM
Clouds: FEW 25000 ft
FM 17:00 - 00:00 UTC
Wind: 230° at 10 kt
Visibility: 6+ SM
Clouds: SCT 25000 ft
Raw TAF: 
TAF KJFK 011936Z 0120/0224 11014G24KT P6SM SCT070 FM012300 10009KT P6SM FEW070 FM020500 VRB05KT P6SM FEW250 FM021300 35008KT P6SM FEW250 FM021700 23010KT P6SM SCT250
Arrival: EGLL
Forecast Valid: Jun 02 00:00 - Jun 03 06:00 UTC
00:00 - 03:00 UTC
Wind: 180° at 10 kt
Visibility: 6+
Clouds: BKN at 1200 ft
TEMPO 00:00 - 06:00 UTC
Visibility: 3.11
Weather: RA
Clouds: BKN at 600 ft
TEMPO PROB 40% 00:00 - 06:00 UTC
Visibility: 2.49
Weather: +RA
BECMG 03:00 - 06:00 UTC
Wind: 250° at 10 kt
Visibility: 6+
Clouds: SCT at 3000 ft
TEMPO PROB 30% 06:00 - 09:00 UTC
Visibility: 4.97
Weather: SHRA
Clouds: BKN at 1400 ft
TEMPO 09:00 - 19:00 UTC
Visibility: 3.73
Weather: SHRA
Clouds: BKN at 1400 ft BKN at 2000 ft(CB)
TEMPO PROB 30% 09:00 - 11:00 UTC
Visibility: 1.86
Weather: +TSRA
TEMPO PROB 40% 11:00 - 19:00 UTC
Wind: 250° at 15 kt gusting to 25 kt
Visibility: 1.86
Weather: +TSGR
TEMPO PROB 30% 19:00 - 21:00 UTC
Visibility: 3.73
Weather: SHRA
Raw TAF: 
TAF EGLL 012306Z 0200/0306 18010KT 9999 BKN012 TEMPO 0200/0206 5000 RA BKN006 PROB40 TEMPO 0200/0206 4000 +RA BECMG 0203/0206 25010KT SCT030 PROB30 TEMPO 0206/0209 8000 SHRA BKN014 TEMPO 0209/0219 6000 SHRA BKN014 BKN020CB PROB30 TEMPO 0209/0211 3000 +TSRA PROB40 TEMPO 0211/0219 25015G25KT 3000 +TSGR PROB30 TEMPO 0219/0221 6000 SHRA
About TAF: Terminal Area Forecasts (TAF) provide detailed 24-30 hour weather forecasts for airports, including wind, visibility, cloud ceiling, and weather phenomena. Updated every 6 hours by NOAA Aviation Weather Center.
Current Airport Weather (METAR)
Departure: KJFK
Temperature: 15°C (59°F) | Dewpoint: 9°C
Wind: 100° at 13 kt
Sky: FEW5500 SCT8000 SCT25000 (Base: 5500 ft)
Flight Category: VFR
Altimeter: 1019.70 inHg (1020 mb)
Observed: Jun 01 22:51 UTC
Raw METAR: 
METAR KJFK 012251Z 10013KT 10SM FEW055 SCT080 SCT250 15/09 A3011 RMK AO2 SLP196 T01500094 $
Arrival: EGLL
Temperature: 16°C (60°F) | Dewpoint: 14°C
Wind: 190° at 10 kt
Sky: OVC700 (Base: 700 ft)
Flight Category: IFR
Altimeter: 1007.00 inHg
Observed: Jun 01 23:20 UTC
Raw METAR: 
METAR EGLL 012320Z AUTO 19010KT 9999 -RADZ OVC007/// //////TCU 16/14 Q1007
About METAR: Meteorological Aerodrome Reports (METAR) provide current weather observations from airports, including temperature, wind, visibility, clouds, and atmospheric pressure. Updated hourly by NOAA Aviation Weather Center. Flight Categories: VFR (Good), MVFR (Marginal), IFR (Instrument Flight Rules), LIFR (Low Instrument Flight Rules).
Route Segment Analysis

The route has been divided into segments of approximately 500km each for detailed analysis.

Route Map With GTG Forecast Overlay
Data Sources & Our Approach
ZeroTurb's Custom Algorithm: Unlike generic turbulence forecasts, we've developed a proprietary ZeroTurb Index (ZTI) algorithm that combines three meteorological indices weighted by their predictive accuracy. This gives you transparent, passenger-focused turbulence probability (0.0-1.0 scale) instead of vague categories. Our approach processes raw ECMWF atmospheric data through custom calculations to detect Clear-Air Turbulence (CAT), wind shear zones, and frontal boundaries that cause bumpy rides.

This forecast integrates data from:

Disclaimer: This forecast is for informational purposes only. Always consult official aviation weather sources and follow ATC guidance.

How accurate are turbulence alerts? Alerts are based on updated forecast models and pilot reports, and can change as departure approaches.

Flight Insights & Recommendations

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