1. CR
CR = Crescent Reef
PI = Pearl Island
CP = Commisioner’s
point
BDA = Bermuda Intl.
BDA CP PI

2. using daily 30-h forecasts
m/s
using daily 30-h forecasts
(first 6 h discounted)
Mean wind (racing hours only) for June 2016 from forecasts

3. Standard deviation in wind speed (racing hours only) for June 2016
m/s

4. using daily 30-h forecasts
WRF low res runs June 2016: selected sites
using daily 30-h forecasts
(first 6 h discounted)
N.B. periodic
behaviour…more later

5. WRF low res runs June 2016: selected sites
Knowing the
wind speed at PI,
you have a reasonable
chance of estimating
speed at CR and CP
wind speed site 2 (m/s)
wind speed site 1 (m/s)

6. comparison of low-res and high-res (AG) runs
No systematic
offsets?

7. How did the (low-res) model perform?

8. ! using daily 30-h WRF forecasts (first 6 h discounted)
Mean daily wind speeds at Bermuda Airport
using daily 30-h WRF forecasts
(first 6 h discounted) !

9. WRF Pearl Island wind speed : June 2016
N.B. time in days
N.B. times and scales in hours

10. day of month (1 – 30) on x-axis
Junes 1981 – from ERA-20C 30 30 30
Speed at Bermuda (kts) 30 30
day of month (1 – 30) on x-axis

11. Wavelet analyses for selected Junes from ERA-20C reanalysis
2010
2009
2008
N.B. times and scales in days
2007
2006
2005

12. MSLP 18Z
ERA-20C
1901 – 2010
(3330 samples)
First 3 EOFs explain
92% of the variance in the data.
MEAN
EOF1
EOF2
EOF3

13. 2006 – 2010 inclusive

14. x
Mean from the re-analysis
… Relation between principal components and wind speeds?

15. June 2016 appears “typical”* in terms of wind speeds and “periodicity”
SUMMARY
June 2016 appears “typical”* in terms of wind speeds and “periodicity”
No systematic differences (found so far) between high-res and low-res runs,
although more rigorous analysis needed.
Low-res runs did well (very well?) at predicting wind speed at BDA
ERA data shows there are detectable patterns (in SLP)
…predictability?
* compared with recent Junes in ERA-20C