Forecast
Digital Map Data:
© Collins Bartholomew Ltd (2006)
Postcode information:
© Royal Mail Group PLC (2006)
Snowdonia: forecast cloud
Saturday, 21 November 2009: dawn to dusk
Overview for Saturday
Outbreaks of light rain at first, followed by strengthening winds and heavy rain later this morning. Around sunset rain clearing away east.
| Hazards | Risk | Explanation |
|---|---|---|
| Blizzards | No Risk | |
| Heavy snow | No Risk | |
| Storm force winds | Medium | A risk of gusts increasing to around 70 mph this afternoon. |
| Gales | High | Southerly winds strengthening this morning. Gusts in excess of 50 mph likely by this afternoon. |
| Severe chill effect | No Risk | |
| Persistent and extensive hill fog | High | Hill fog is likely to become extensive above around 600 metres this morning, clearing later. |
| Thunderstorms | No Risk | |
| Heavy persistent rain | High | Rain is likely to be heavy and persistent from late morning. |
| Dawn to 0900 | 0900 to 1200 | 1200 to 1500 | 1500 to dusk |
 Light rain |
Light rain |
 Heavy Rain |
Heavy Rain |
| 20% | 80% | 90% | 40% |
Detailed mountain weather forecast: Snowdonia
Saturday
Weather
A cloudy start with outbreaks of mostly light rain. The rain becoming heavier later this morning as southerly gales develop over the higher ground, with hill fog becoming extensive. Late afternoon, around sunset, drier and clearer weather arriving from the west.
Visibility
Moderate or poor for much of the day in rain and very poor in hill fog.
Hill fog
Occasional patches above around 300 metres at first, mainly in the east. Becoming widespread or blanket above around 600 metres later this morning, then clearing from the west around sunset.
Maximum winds above 500m
Wind gusting 60 to 70 mph this afternoon above around 600 metres.
Temperature
| Valleys | Plus 13 Celsius. |
| 900 m | Plus 8 Celsius. |
| Freezing level | Well above the summits. |
Sunday
Weather
A very windy day. Bright or sunny spells are likely at times with broken cloud but there will be frequent blustery showers, heavy and sometimes prolonged, especially in the afternoon. Gale or perhaps severe gale force south or southwest winds. Occasional hill fog.
Visibility
Moderate or good but occasionally poor in heavier showers and very poor in hill fog.
Hill fog
Occasional above around 600 metres with patches at 400 metres in heavier showers.
Maximum winds above 500m
Wind gusts 70 to 80 mph possible at times above around 600 metres.
Temperature
| Valleys | Plus 10 to plus 12 Celsius. |
| 900 m | Plus 6 Celsius. |
| Freezing level | Well above the summits. |
Outlook
Monday
Unsettled with further showers or perhaps some longer spells of rain. Strong to gale force westerly winds. Occasional hill fog.
Tuesday
Continuing unsettled with further showers or perhaps some longer spells of rain. Strong to gale force westerly winds. Occasional hill fog.
Wednesday
Another unsettled and windy day with occasional blustery showers and occasional hill fog.
Languages
Read this page in: Cymraeg
RSS Warning and advisories
Regional warnings and advisories feeds
Orkney & Shetland
Highlands & Eilean Siar
Grampian
Strathclyde
Central, Tayside & Fife
SW Scotland, Lothian Borders
Northern Ireland
Wales
North West England
North East England
Yorkshire & Humber
West Midlands
East Midlands
East of England
South West England
London & South East England
Weather gadgets
Vista weather gadget
Firefox weather gadget
Related internet links
Avalanche Information for Scotland
The Met Office is not responsible for the content of external internet sites.
Advertisement
