U.S. natural gas inventories seen up 91 bcf in Thursday EIA report37 minutes ago by Thomson Reuters

* Injection estimates range from 82 bcf to 106 bcf    * Median build in the poll is 91 bcf    By Joe Silha    NEW YORK, May 22 (Reuters) - U.S. natural gas inventories onaverage are expected to have gained 91 billion cubic feet lastweek, a Reuters poll of industry traders and analysts showed onWednesday.    Utilities typically stockpile natural gas from April throughOctober, then withdraw stored supplies from November throughMarch to help meet peak winter heating demand.     The U.S. Energy Information Administration will release itsgas storage data for the week ended May 17 on Thursday at 10:30a.m. EDT (1430 GMT).    The Reuters poll had 21 participants, with injection estimates ranging from 82 bcf to 106 bcf. The median build inthe poll was 91 bcf. It would be the sixth injection of thestock-building season, which started about three weeks laterthan usual this year due to chilly spring weather.    Stocks rose by an adjusted 75 bcf during the same week in2012. The five-year average gain for the week is 90 bcf.    The U.S. National Oceanic and Atmospheric Administrationsaid there were 34 heating degree days last week. That was two fewer than in the previous week and three fewer than normal but12 colder than the same week last year.    NOAA also showed 24 cooling degrees last week, four abovenormal and four more than in the same year-ago week.    Degree days, or the number of degrees Fahrenheit that aday's average temperature varies from 65 degrees Fahrenheit (18Celsius), are used to estimate demand to heat or cool homes andbusinesses. They are often weighted to reflect populationdifferences in specific states and regions.    For the week ended May 10, overall storage rose 99 bcf to1.964 trillion cubic feet.     Most traders viewed the build as bearish for prices, notingit came in above the Reuters poll estimate of 95 bcf and wellabove the five-year average increase for that week of 83 bcf.    (Storage graphic: http://link.reuters.com/mup44s)    The build, which exceeded market expectations for the thirdstraight week, reduced the deficit relative to last year by 43bcf to 694 bcf, or 26 percent below last year's record highs atthat time.    It also trimmed the shortfall versus the five-year averageby 16 bcf, leaving stocks at 83 bcf, or 4 percent, below thatbenchmark.    A build on Thursday at the Reuters poll average estimatewould shrink the deficit to last year by 16 bcf to 678 bcf, or25 percent. It would also trim 1 bcf from the shortfall versusthe five-year average, leaving stocks at 82 bcf, or 4 percent,below average for that week.    In the last four reports, total stocks rose 260 bcf, or 65bcf per week, versus a 160 bcf build for the same one-monthperiod last year and a 269 bcf five-year average gain for thatperiod.    NOAA said it expects 42 cooling degree days this week, 15more than normal and four more than the same year-ago week. NOAAexpects just 10 heating degree days this week, 18 below normaland one less than the same week in 2012.    Early injection estimates for next week's storage reportrange from 80 bcf to 103 bcf, versus a 72 bcf build during thesame week last year and a five-year average increase for thatweek of 92 bcf.    Storage peaked last year at 3.929 tcf in early November, thefourth straight year in which gas inventories headed into theheating season at an all-time high.    Stocks ended March at 1.683 tcf, or 32 percent below lastwinter's record high finish of 2.48 tcf.    Injections during the April-through-October stock-buildingseason on average total about 2 tcf, meaning stocks could headinto next winter with about 3.7 tcf in the ground, well abovewhat would be needed to meet even the coldest winter demand.    The following is a partial list of forecasters in thisweek's survey. If forecasters gave a range, the midpoint wasused. Numbers in billion cubic feet (bcf).          Asset Risk Mgmt           +  91    Citigroup                 +  91    Citi Futures              +  87    Ecova                     +  91    Energy Management Inst    +  90    enerjay LLC               +  89    FirstEnergy               +  87    Guernsey                  +  99    IAF Advisors              +  92    INTL FCStone              +  92    JPMorgan                  +  94    Prestige Economics        +  85    Raymond James             +  94    RideFar Energy            +  93    Schneider Electric        +  92    The SMC Report            +  91    Stephen Smith Energy      +  86    Thomson Reuters Analytics +  82    Tradition Energy          +  90     (Reporting by Joe Silha; Additional reporting by EileenHoulihan; Editing by John Wallace)