Weather

Weather Forecasting for flying the Blue Mountains

Links to useful weather forecasting tools

Live Weather Observations

With the support of the NSWHPA we have installed a weather station at Mt Blackheath.

Forecasts

These resources are useful for forecasting flying conditions in the Blue mountains and central tablelands:
As the season starts to warm up again, pilots should check the seabreeze forecast. A sea-breeze front can bring turbulent and dangerous flying conditions to the Blue Mountains. This sometimes occurs without warning, but generally the approaching front can be identified by haze and clouds coming in from the East. Having the sea-breeze forecast in mind may help identify the change in the weather approaching.

General guide to weather forecast for Mt Blackheath

1. Chat to local experienced pilots.

This will give the best idea if there is suitable conditions for the day and will give you someone to fly with. Take care as there can be strong thermic conditions all year round.

2. BOM forecast for upper Blue Mountains

Sunny, mostly sunny, and partly cloudy are generally good forecasts. Light westerly winds are the preferred wind strength and direction. However, the forecast generally only says "Light winds", so you will need to look below to find out where to see the direction of these light winds. Westerly 15 to 20km/h can be good in the winter months when there is less thermic activity, but at many times of the year indicates that you will need to make a call if you feel it is safe for you to fly in those conditions, and many pilots will choose to stay on the ground. Westerly stronger than 15 to 20km/h is probably blown out. 

From Spring through till autumn, keep an eye out in the forecast for an easterly change, which probably represents a sea-breeze coming through, potentially turning the valley containing the LZ into a washing machine. The wind forecasts on BOM are generally more accurate for wind strength at Blackheath than Windfinder or Weatherzone.

3. Weather observations

Mt Boyce is the closest BOM weather station to the Mt Blackheath launch. It also has a live weather camera that looks directly across the valley to Mt Blackheath. The West launch is not visible but the North cliffs are visible. Generally paragliders are too small to be visible in the camera when in front of launch. 

The club has a weather station on the takeoff. When the thermals start, the wind direction graph shows a sudden variability in the wind direction. It is very obvious in the example below (12h period of observations). Thermals started at about 11:00AM. The thermals generally start on the North spur, and this is seen below as the initial dip before the direction returned to West. The arrival of the sea-breeze is seen at approximately 4:30PM and lasted for several hours. Overnight the wind returned to the steady meteo winds. This graph was from 24 May 2019, so a sea-breeze can occur late into the colder part of the year



Generally, due to the thermals, the usable wind speed should be lower than coastal sites and the wind will have stronger gusts. If you are considering waiting for a glass-off on a blown out day, one good indicator of the winds decreasing is when the forecast for the next day is to have lighter winds, you will have more chance of a glass-off at the end of the day. However this is no guarantee that a glass-off will occur.

4. Seabreeze

Especially during summer months (but can be any time), sea-breeze fronts can bring turbulent and dangerous flying conditions to the Blue Mountains. These sometimes occur with little warning, but generally the approaching front can be identified by haze, a cloud line and / or a step-down in cloudbase. The sea-breeze can be seen in the windy.com forecast and sea-breeze.com forecasts. Checking seabreeze.com.au for strong afternoon sea-breeze is another way of gathering info about the possibility of the Easterly wind hitting Blackheath. People not flying can also check weather observations from Penrith, and Katoomba throughout the afternoon.

5. AUSRASP

Mt Blackheath is now labelled as a site on the map:



  • "BL Average wind" - Zero to 8 knots westerly is generally a good bet (Dark blue to baby blue). Pale green can be fine, but if / once it gets thermic it can be touch and go depending on your experience in rough air. Middle green generally indicates blown out.



  • "Height of Critical Updraft Strength" - Predicted height of top of climbs. "Thermal Updraft Velocity" - Predicted average climb rate. 200 feet / minute is 1 m/s. Be prepared for some rock and roll if it is yellow or stronger. Peak climb rates might be double or more than the average. For example, an unusually strong day with predicted thermal strengths of 800 feet / minute might provide bullets of 8+ m/s peaks and sharp edges.



  • "BL Cloud Cover" - Is it predicted to over-shadow during the day?



  • "CAPE" - Is it likely to OD?



  • "Wind at BL Top" can be good to look at - if this is showing it is windy at this level, and the thermal tops are not too high, then you can get an idea that the wind gradient profile might be pretty fierce. Again, look for an easterly change pushing in from the coast. Look at where the convergence is in relation to the bottom of the R.
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