This document provides a weather briefing and forecast for Wellington, New Zealand for May 18th through May 21st, 2012. Recent weather observations and forecasts from last week are presented and validated. The current weather situation as of Friday morning is analyzed using surface maps, satellite imagery, and radar. Forecasts for Friday through Saturday generated by the 12km NZLAM model are shown. A 2-day and 6-day forecast for Wellington Airport is also presented. The summary predicts showers on Friday with south winds up to 25 kts, light showers and south winds around 20 kts for Saturday, dry conditions and light variable winds on Sunday and Monday.

1. Weekend Weather Briefing
18th May 2012
This slide was presented by Stuart
Moore from Niwa on 18 May. I have
added comments and explanations in
clouds like this one
Data from:

2. Last week’s forecast
• Fri 11th: Tmax: 13.1ºC, Tmin: 8.6ºC, Windmax: 10.4kts, Windmin:
1.2kts, Mean dir: S
• Showers clearing, Mod-fresh S, Tmax 13ºC
• Sat 12st: Tmax: 14.8ºC, Tmin: 6.4ºC, Windmax: 17.7kts, Windmin:
2.3kts, Mean dir: N
• Fine, early low cloud lifting, N freshening PM, 11-15ºC
• Sun 13th: Tmax: 17.6ºC, Tmin: 13.1ºC, Windmax: 17.3kts, Windmin:
10.5kts, Mean dir: N, 5mm rain up to 9am Monday
• Fine at first, showers from midday,
• fresh N strengthening, 13-16ºC Previous week’s forecast
validation. Red is obs from
Wellington Airport, Black is the
EcoCx forecast
• Mon 14th: Tmax: 15.6ºC, Tmin: 13.0ºC,
• Windmax: 25.9kts, Windmin: 12.1kts, Mean dir: N

3. Last week’s forecast
Plots comparing EcoConnect
forecast against obs for
Wellington Airport for 3
forecast periods over the
previous weekend.

4. Current Situation
Surface analysis, 0600hrs
Latest (Friday AM) MetService
Surface analysis and IR
magery
IR, 0600hrs

5. Current Obs – 0600hrs
Current (Friday AM) weather
obs from MetVUW

6. Radar Observation @ 0805
Latest (Friday AM) MetSerive
NZ radar

7. Fri 12pm
EcoConnect forecast
from 12km NZLAM
NWP model

8. Fri 6pm
EcoConnect forecast
from 12km NZLAM
NWP model

9. Sat 6am
EcoConnect forecast
from 12km NZLAM
NWP model

10. Sat 6pm
EcoConnect forecast
from 12km NZLAM
NWP model

11. “Fuzzy precip” from MOS
output suggest chance of
light showers through to
Sat PM

12. 2-day Wellington Wellington 2-day Forecast
Airport meteogram
from 12km
esolution NZLAM
model)
dir for
Wi tion
an see )
ec ce
nd
d
slid
(
e5

13. Wellington 6-day
Wellington 6-day Forecast
orecast (from Met
Office global model
ata)

14. Wellington Summary
Summary for next
ouple of days
•
Wellington Airport) Today (18th):, 10-15ºC, S winds increasing to 20-25kts, possible
ompared to
MetService forecast
showers around midday
• Sat 19th: 9-12ºC, S continuing around 20kts but easing in late
PM, possible light showers through the day
• Sun 20th: 10-12ºC, S easing further to light winds, staying dry
• Mon 21st: 10-12ºC, S through day to N by late PM, staying dry