1. A CLIMATE STUDY of ABOVE and BELOW NORMAL TEMPERATURES ALONG with LONGEVITY (Is there a Pattern?) Matthew Masek (WFO North Platte, NE)

2. OUTLINE Data Set Above and Below Normal Average Temps –A look at the numbers –Patterns/Signals?? Consecutive Days –Above/Below Normal Average Temps –20+ Days, 25+ Days, 30+ Days By Years (pattern/signal??) By Time of Year - Months (pattern/signal??) Final Thoughts

3. DATA SET North Platte (LBF) – (used exclusively) Existing Data Set –Sept 18, 1874 to Present Used –Jan 1, 1875 to June 30, 2006* (131.5 Years) Ignored Site and Equipment Changes Allowed Average T to have.5

4. DATA SET 30 Year Normal for Average T –1970 to 2000 –Assumed representative 1870s & 2000s (decades) –Estimated based on partial record

5. INSIDE THE NUMBERS Total Days in the Study –48,028 Days Average T Above Normal –25,650 Days (53.4%) Average T Below Normal –21,381 Days (44.5%) Average T Equal Normal –997 Days (2.1%)

6. INSIDE THE NUMBERS Difference between Above and Below –4,269 Days –Over 11.5 Years –Remember ONLY 131.5 Years in Set That’s 9% more Above Days than Below Days

7. How Can That Be? Departure of Average T from Normal CAN be More Significant when Below than Above February 11, 1899 –High -13, Low -29 –Average T = -21 degrees (normal 28 degrees) –Departure from normal 49 degrees December 23, 1964 –High 74, Low 34 –Average T = 54 degrees (normal 24 degrees) –Departure from normal 30 Degrees 279 days with departure below normal 30+˚279 days with departure below normal 30+˚

14. Below Ave T Above Ave T 5 years with most  1978 - 222 (60.8%)  1996 - 216  1967 - 212  1993 - 211  1951 - 206 5 years with least  1934 - 86 (23.5%)  1931 - 107  1900 - 108  1939 - 109  1938 - 110 5 years with most  1934 - 276 (75.6%)  1931 - 253  1933 - 251  1938 - 250  1939 - 248 (tied with 1900) 5 years with least  1978 - 131 (35.8%)  1996 - 139  1967 - 141  1993 - 144  1951 - 148

19. Trends 30s were definitely HOT Fairly constant last 10 years Signs of Global Warming (not really) –Remember this is not looking at magnitude just number of days

20. Consecutive Days Allowed for crossover Jan 1 Based on above or below the normal average T – NOT based on Magnitude –2 degrees or 30 degrees above (don’t care) Winter 2005-2006 set new record for consecutive days with average temp above normal (49 days) 20+ days, 25+ days, 30+ days (trend???)

24. Time of Year Winter months are when long consecutive streaks have been set For 30+ day events - all but one during the months from November-April –Ended July 14 1933 (31 Days)

28. Final Thoughts Wish there was 200 - 300 Years of Data Limited Patterns/Signals Causes - Unknown History Repeats – –Doubt a 30+ days event of below normal ave T –20-29 days event possible Next –Look at magnitude overall and during streaks Average High and Average Low –Add more sites to see if pattern is widespread

29. THE END ????