However, If they become negative for a long period, that could mean a very cold winter for the north. These indices have been negative for the last several winters and some research suggest these indices may stay in overall negative or positive phases for several years at a time.
We must also remember that storm development and tracks through the midwest are critical in the winter for determining where the heaviest precipitation will occur and in what form it will fall. La Nina tends to shift storm tracks a little further south compared to normal, with the Ohio River Valley region being a favored area for winter storms.
This places our region on the very northern edge of many winter storms. After looking at research based on a national scale and the CPC's winter outlook, a local research study was completed to look at how past La Nina events affected the local area.
Since , there have been 14 documented La Nina episodes. Because of a limited dataset and local climate variability, these results alone cannot predict exactly what will happen during the current La Nina episode, but it is interesting to note the trends. Monthly average temperatures, precipitation, and snowfall data for each episode was compiled for Fort Wayne and South Bend.
The graphs that follow show the departure from normal of all the La Nina episodes combined. In general, Fort Wayne was warmer than normal for all months except March, May, and November which were colder than normal during La Nina episodes.
In terms of precipitation, the months of January, February, May, August, and October were wetter than normal while the remaining months were drier than normal. In general, South Bend was warmer than normal for all months except February, March, and May which were colder than normal during La Nina episodes. In terms of precipitation, the months of January, February, April, August, and October were wetter than normal while the remaining months were drier than normal.
Check back each month as monthly averages from the current La Nina episode will be added to the graphs! The winter season was cooler and drier than normal but snowfall was above normal at both Fort Wayne and South Bend as a moderate to strong La Nina episode was occuring. The winter proves why you cannot use forecasts of precipitation to imply potential snowfall amounts. The average temperature was 5. This puts the winter season average temperature 3.
Precipitation was also below normal for both December and January 1. February featured above normal precipitation 1. For the winter season, precipitation was below normal by 0. While precipitation was below normal, snowfall was above normal for all 3 months. Snowfall was 2. February ended as the 2nd snowiest February on record with The seasonal snowfall total of The average temperature was 4 degrees below normal for December, 2. The winter season average was 2. Precipitation was also below normal for both December 1.
The winter season total precipitation was 0. Snowfall was 4. January snowfall totaled This makes it the second snowiest January on record behind January Snowfall for February was There have only been two other winter seasons and that have had or more inches of snow. Through February 25th, the winter season was warmer and wetter than normal but had below normal snowfall at both Fort Wayne and South Bend as a weak to moderate La Nina episode was occuring.
Like the previous winter, the winter proves why you cannot use forecasts of precipitation to imply potential snowfall amounts. The average temperature was 6. This puts the winter season average temperature 4. Precipitation was also above normal for both December and January 1. So far, February has featured below normal precipitation 0. For the winter season, precipitation was above normal by 1.
The routes of aircraft flying long distances at high elevations are heavily influenced by these winds, as the planes use them to advantage when flying to the east, and do their best to avoid them flying west.
The movement of air masses is quite complex, but a simplified version is that when those lobes extend far to the south, cold air from the north can penetrate to those regions, as happened in October. The position of the jet stream also determines the likely path of storms. Thus, when we see weeks go by with storms passing along the same path whether it over us or over the Washington-New York corridor it is because the configuration of the jet stream is remaining in a similar place see image below.
We have experienced mostly sunny, pleasant winter weather while the mid-Atlantic region has been socked largely because the jetstream remained in that position. All of these are wonderful examples of the fascinating variability in weather, as opposed to climate. But we can never say that any blizzards, hurricanes, cold snaps, hot spells, tornados, or even a season of unusual weather phenomena, result from anthropogenic human-caused greenhouse warming.
The consequences of our massive additions of heat-trapping material to the atmosphere will be significant, but they will be evident only in statistical patterns that demonstrate changes that span extended periods of time.
Then we will be in climate. That and the data from the warm few decades that preceded it are the beginning of the kind of record that will provide perspective about long-term changes in climate. But even these sequences are influenced by a number of other complexities of our climate. Calendar Give News Find us Contact.
Maine Climate News. Home Resources News About Us. January was also warmer than normal for most of the state, but the precipitation varied greatly; the east slopes of the Cascades and most of central WA was dry while the rest of the state was either at or above normal for precipitation. By the end of January, the snowpack in the Cascades was below normal for that point in the season. Precipitation was still below normal, but a few of the storm systems brought needed snow to the mountains.
March was extremely wet for many portions of the state and the cool, active weather pattern brought heavy snow to the mountains. Snowpack statewide built to normal to above normal depths from the end of February through March. Seasonal totals of lowland snow varied around the state and did not fit into a clear pattern. Table 1 shows Nov-Mar total snow for several WA stations as well as the normal. Many stations east of the Cascade Mountains had close to normal or above normal total snowfall for November through March.
Seasonal snow totals tended to be near-normal on the west side of the Cascades. Note that the Bellingham snow normal was taken from the Bellingham International Airport site. In summary, the fall forecast for a relatively cool and wet winter for WA was an accurate one, though the temperature anomalies were perhaps not as strong as initially thought.
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